Design and Experience of Mobile Applications: A Pilot Survey

Abstract

With the tremendous growth in mobile phones, mobile application development is an important emerging arena. Moreover, various applications fail to serve the purpose of getting the attention of the intended users, which is determined by their User Interface (UI) and User Experience (UX). As a result, developers often find it challenging to meet the users’ expectations. To date, several reviews have been carried out which explored various aspects of design and the experience of mobile applications using UX/UI. However, many of these existing surveys primarily focused on only some of the issues in isolation but did not consider all the major parameters such as visualisation/graphics, context, user behaviour/emotions/control, usability, adaptability/flexibility, language, and feedback. In our pilot survey, we gathered the preferences and perceptions of a heterogeneous group of concerned people and considered all the aforementioned parameters. These preferences would serve as a reference to mobile application developers, giving them useful insights. Our proposed approach would help mobile application developers and designers focus on the particular UI/UX problems of mobile applications as per their relevant context. A comparative analysis of the various UI and UX factors that determine a mobile application interface is presented in this paper.

1. Introduction

Mobile phones are the most easily accessible hand-held devices used by the current generation. In 2021, global mobile phone shipment volume is predicted to reach 1.65 billion units, 6.3% higher than the previous year, while smartphone shipment volume is expected to increase 7.8% to 1.8 billion units in 2022. As a result, the Compound Annual Growth Rate (CAGR) for mobile phones and smartphones is anticipated to be 2.34% and 3.62%, respectively, during 2020–2025. According to [1], the global mobile application market was valued at USD 154.05 billion in 2019 and is expected to grow at a CAGR of 11.5% between 2020 and 2027. According to CAGR, the UI industry will grow by 16 percent during 2017–2027, reaching USD 50 billion. Figure 1 shows the technological revolution in the smartphone industry by estimating the number of smartphone users worldwide and the global market size of mobile applications [2].

The growing world of mobile phones and their applications at our fingertips requires better mobile interfaces that help to efficiently connect the physical world with the virtual world. The front-end of mobile applications has improved a lot over the years. Mobile phones and their increasing usage have transformed the conventional design into the user-oriented design of mobile applications. With the rise of chatbots, the Internet of Things (IoT)-based mobile applications, recommendation systems, and many more require a strong yet effective UI and UX to let users engage with the system. The seamless connectivity of the user with the system has to be the utmost priority of any mobile developer. A lot of research and analysis has been performed by the scientific community in this area. However, only a few have provided a concrete UI/UX guide to the mobile application developer. This paper lets its readers know the terms and guidelines to be followed for designing an eye-pleasing and mind-easing user interface and experience.

1.1. Motivation

Hiring creative UI/UX designers apart from application developers (at an early stage) might not be feasible for new startups. Hence, the developers tend to design the interfaces on their own. Having less experience in this field often leads to excessive time involvement of the developers, decreasing the developer’s overall efficiency. This paper aims to help UI/UX enthusiasts and mobile application developers design decent applications that can keep up with the basic requirements of the mobile application. Furthermore, more depth and wider concerns need to be addressed while building an interactive application, which comes with more exploration and experience.

The UI/UX design process includes transforming general ideas into user-specific scenarios. This process includes the pre-design stage, design research, sketching, wireframing, visualization, and slicing [3]. Moreover, several UX design tools are available in the market, giving the developers a choice to find the best rapid prototyping software, such as Figma, Sketch, Framer, Webflow, Principle, Atomic, and Proto.io tools [4]. Moreover, Usability Metric for User Experience (UMUX) is a qualitative assessment designed to measure the usability of a system that primarily focuses on efficiency, effectiveness, and satisfaction. The System Usability Scale (SUS) is an omnidirectional standard usability questionnaire that calculates a system’s usability [5].

This paper helps the developers by letting them understand all the ’how-to’ required while designing the front-end interface of mobile applications. Endowing the developers with this knowledge is a must while designing and implementing the layout of the mobile application interfaces. Hence, the proposed scheme of this paper deals with letting the front-end mobile application developers, with little or zero knowledge of designing the UI and the UX, gain a basic understanding of it.

1.2. Research Contributions

The main contributions of this paper are as follows.

• We gathered the preferences and perceptions of a heterogeneous group of concerned people. These preferences would serve as a reference to mobile application developers, which gives them useful insights.
• We propose a novel approach that will help mobile application developers and designers focus on particular UI/UX problems of mobile applications as per their relevant context.
• We discuss a comparative analysis of various UI and UX factors that determine a mobile application interface.
• An analysis of users’ necessary context-based wants and preferences is also elaborated. A detailed survey of what the users want was conducted, and its systematic analysis has been extensively explained.

1.3. Article Layout

This article is organized into five sections as illustrated in Figure 2. Section 2 presents the existing state-of-the-art schemes. Section 3 presents the taxonomy: the basic building blocks of the UI and the UX. Section 4 presents the result, and finally, Section 5 concludes the article.

2. State of the Art

This section presents the state-of-the-art approaches taken to evaluate the existing works done in this arena.

Table 1. Comparative survey of state-of-the-art.

Ref.	Year	Objective	Pros	Cons	1	2	3	4	5	6	7
Our proposed paper	2022	To study the effect of social media content on engagement behaviour of users	Analysis of the necessary context-based wants and preferences of users is discussed in the paper	Gives a general overview of UI/UX for mobile applications	●	●	●	●	●	●	●
[6]	2022	To propose an end-to-end evaluation framework for mobile application	Provides an end-to-end evaluation framework "perses" which was integrated into a DevOps to automate its execution	Heterogeneity of the scenario is missing	●	●	●	●	●	●	○
[7]	2022	To study the accessibility barriers in mobile apps	Proposes guidelines to prevent these issues.	The study specifically meant to mobile application development and not for UI/UX.	○	●	●	●	●	●	●
[8]	2022	To evaluate the dynamism of the digital content and tools used in mobile application development	Provides accessible projects	unpleasant interactions	○	●	●	●	●	●	○
[9]	2021	Investigated the effect of sequence of UI elements and type of forms	Effect of sequence of UI elements and type of forms	A very primitive design	●	●	●	●	●	○	○
[10]	2021	To conduct research to evaluate and explore the impact of the need for uniqueness, self-identification, and perceived performance risk on mobile application usage behaviour, and the mediating function of attitude toward mobile application design	Contains literature and information about different consumer perceptions and their impact on usage behaviour, giving helpful insights to application developers	Limited context, sample size and variables under consideration	○	○	●	●	○	○	○
[11]	2021	Using design thinking to produce a design that meets the needs of each user to achieve Goal 4 of the Sustainable Development Goals (SDGs)	Created a prototype of the UI/UX design for "IdeIn," a web-based learning tool that strives to give equal access to quality education for all students	Limited context, region of interest and scope.	●	●	○	●	●	●	○
[12]	2021	To study the effect of social media content on engagement behaviour of users	Analyses how content and context affect the link between each type of material and user engagement and thereby proposed research hypotheses	Research restricted to two social media platforms, which may be commonly used on desktops	○	●	●	○	○	●	○
[13]	2019	To produce a form of experience in making a usability chemical application, using concepts of the UX	Gives useful insights for mobile application development using UX analysis	Restricted to chemical applications	○	○	○	●	○	○	○
[14]	2019	To offer a proposition for an agrarian information gathering framework that spotlights on UI and client experience (UI and UX) from all stakeholders	Extendable to other agricultural applications	Context limited to agriculture	●	●	○	●	●	○	●
[15]	2018	To propose a UI/UX tool and methodology (domain and device-independent model-based adaptive UI methodology	Provides personalized services for various applications to improve the UX to meet the right level of user satisfaction	A rule-authoring tool for managing complex adaptation rules, as well as an unresolved UI presentation issue	●	●	●	●	●	○	●
[16]	2018	Prepare UI/UX and agile approaches for the design and deployment of a job tracking and assessment system.	Took Agile methodology and KPIs into consideration	Job domain specific research	●	●	●	●	●	○	○
[17]	2017	UI/UX research and design for a mobile e-commerce application prototype on Gramedia	Analyses the user’s preferences and create a mobile application prototype	Restricted to e-commerce	●	●	●	●	○	○	●
[18]	2017	User interface generation by sketching	Obtaining a collection of sample graphical user interfaces (GUI) from existing open source programmes that are similar to or identical to an original designer’s draft for an interface	Code search engines to be improved	●	○	●	●	●	○	○
[19]	2017	Design and construct a user-friendly mobile application that provides information and appeals to users	Competitive analysis, card sorting, personas, site mapping, wireframes, user testing, branding, and focus groups are all factors in the creation of mobile applications	Focus on UI missing	○	●	●	●	●	○	●
[20]	2016	An organised investigation of the user experience of mobile apps	Assist application developers and designers in concentrating on specific user interface and user experience challenges	Focus on UI missing	○	●	●	○	○	●	●

●: Area covered in the surveys; ○: Area not been covered. 1. visualisation/graphics; 2. context, 3. user behaviour/emotions/control; 4. usability; 5. adaptability/flexibility; 6. language; 7. responses/notifications/feedback.

briefly explains those approaches. The existing literature provides a lot of detail about the UI and the UX. The papers considered in the tabular comparison have been carefully selected keeping in mind the myriad of knowledge bases that they touch upon. Carefully designed literature is widely available and can help intermediate developers with a certain knowledge of design. However, for a beginner non-designer developer, it becomes challenging to develop a mobile application from square one without getting confused. A one-stop solution is required for those developers. Some of the literature, as discussed in Table 1, is beautifully written, discussing various knowledge domains for UI/UX designing. However, concise basic knowledge essential for a beginner to understand seems to be missing. Research papers focus on a multitude of aspects of UI/UX designing. However, it was observed that the mentioned seven points seem to have quite a high preference when it comes to the users. The authors wanted an inclusion of both visual and mental acceptability of mobile applications that made sense in today’s world. There are so many papers, books, and conceptual studies available that dive deep into the subject, but for a beginner, it often becomes daunting to understand a tonne of concepts at once. This paper is an aid for developers searching for literature for basic knowledge of UI/UX.

According to [6], a heuristic evaluation is a usability inspection method which identifies the usability problems in UI design. It examines the interface and judges its compliance with recognized usability principles, i.e., heuristics. A major objective of heuristic evaluation is to identify various design-related problems in the UI. Authors have proposed an end-to-end evaluation framework "perses" for mobile applications which were integrated into a DevOps to automate its execution, but it fails to provide a heterogeneous scenario. Moreover, [7] evaluated the dynamism of the digital content and tools used in mobile application development. In the same way, authors in [8,9,10] investigated the effect of the sequence of UI elements and type of forms, the impact of the need for uniqueness, self-identification, and perceived performance risk on mobile application usage behaviour. Authors in [11], proposed a prototype of the UI/UX design for "IdeIn," a web-based learning tool that strives to give equal access to quality education for all students, but it had limited context, interest, and scope. According to [12], the authors analysed the effect of social media content on the engagement behaviour of the user. Authors in [13] provide useful insights for mobile application development using UX analysis. Authors in [14,15], proposed a UI/UX tool and used a domain- and device-independent model-based adaptive UI methodology, which provides personalized services for various applications to improve the UX to meet the right level of user satisfaction. This is a rule-authoring tool for managing complex adaptation rules, as well as an unresolved UI presentation issue.

To date, several reviews have been carried out that explored various aspects of design and experience of mobile applications using the UX/UI. The proposed survey spans from 2016 to mid 2022. However, many of these existing surveys primarily focused on several issues and did not consider all the major parameters such as visualisation/graphics, context, user behaviour/emotions/control, usability, adaptability/flexibility, language, and feedback. The existing surveys focus on these parameters only in isolation. There is a tremendous need to perform a comprehensive survey, which focuses on all the aforementioned contexts.

3. Taxonomy: Design and Experience of Mobile Applications

In this section, we discuss a solution taxonomy: the design and experience of mobile applications. Figure 3 depicts the detailed layout of the same.

3.1. Basic Building Blocks of the UI and UX

In this section, we discuss the basic building blocks of the UI and UX to give insights about the role of the UI and UX in mobile applications, a comparison between the UI and UX, and the role of the UI/UX for designing mobile applications in detail.

3.1.1. Role of the UI in Mobile Application

The User Interface is the way a mobile application appears to its users, along with its visual design. The primary controller for determining the appropriateness of a user interface is the target audience and the context of the mobile application. Now, the question is, what really is meant by context? In a unique wireless environment characterized by mobility, flexibility, and personalization, [21] defines context as any real-time information or entity (can be a user, a location, a time, an action, or an item) that influences the interaction between mobile device users and mobile applications, as well as potentially changing the preferred behaviour of those applications. To find the application’s context, we may think: “What is the main user base”? The best interface is the one which is very close in terms of the relationship to its context. User interface design becomes an effective one only when the communication of the user with the system is effortless; that is, the system improves rather than obstructs the workflow and encourages the active involvement of its users [22]. The user interface also refers to the subjective psychological sensations that users generate while using products or services, such as their beliefs, feelings, desires, attitudes, physiology and psychology, behaviour, and so on, and it spans the front, middle, and late stages of service or product usage [23].

The aesthetics of any mobile application are determined by the various frameworks used. Currently, the most often used frameworks are dart, React.js, JavaScript, Cordova, Java, Swift functionalities in a flutter, Kotlin, React Native, Ionic, and Xamarin environment. A pleasant UI enhances the user experience, with the utmost priority given to effective interfaces, yet keeping the design simple [24]. For any non-designer programmer, application development is a tough one. A non-designer does not have common designing knowledge but has moderate coding knowledge. So, it is necessary for the front-end developer to have an understanding of basic UI fundamental elements. Several constraints [24] must be addressed when designing the UI for any mobile application.

• Technology-related (device-related) constraints: Supporting Operating System (OS) version, limited processing power, screen size, and resolution.
• User-related constraints: Limited attention spans during mobility, changing locations and context.

According to the current trends, Adobe XD, Adobe Illustrator, Figma, and Sketch are the most used software platforms for designing the interactive interfaces of application prototypes. Various UI kits are readily available on numerous platforms to offer drag and drop facilities that help when a user interface is to be prepared in a short time while maintaining the UI/UX standards. This is the most effortless way for beginner front-end developers to design the mobile application all by themselves. The key interface combinations are haptic and have audio/visual experience. The main goal is Following the eye, i.e., preventing the users’ eyes from diverting and letting their minds stay focused. NetBeans, Visual Studio, and Eclipse are some of the modern development environments that support UI generation [18]. In addition, some technologies allow users to utilize sketches as input to create stunning user interfaces such as JavaSketchIt, SILK, MobiDev, and REMAUI. Moreover, UI integration is an equally important component to be considered for mobile application development [25].

3.1.2. Role of the UX in Mobile Application

The term ’User Experience’ is not restricted to any aspect but has many meanings attached to it [26], ranging from traditional usability to beauty, cognitive-driven, experiential, and effective technology use. In simple terms, the UX is all about how the mobile applications perform their functionality. It wants to know how “effect” plays a part in the technology used as an antecedent, a consequence, and a mediator. Furthermore, it places a strong emphasis on happy feelings. One of the key motives of a cognitive-driven perspective on Human–Computer Interaction (HCI) is to prevent any frustration or dissatisfaction amongst the users [27]. The intention of HCI design is to make the interaction between the system and the user feel more natural. It will make the user’s experience more enjoyable in the long term. Giving a positive experience to the users enables them to seamlessly interact with the mobile interface without any hindrances [28]. Experience, function, and form have a triangular relationship where they are all connected. Aesthetics and functionality must understand the psychological and behavioural patterns of the target user(s), which plays a major role in the UX/UI [10].

To create an efficient UX-based mobile application, appropriate planning needs to be followed by utilizing the essential benefits of the UI features [29]. A fun experience categorization such as PLEX during the creation and assessment of interactive mobile applications may aid in concentrating on the joyful parts of the UX, which in turn may help in defining goals for experience-driven personal product design [30].

Additionally, context-aware mobile applications are used to enhance the UX by evolving the user input, i.e., it perceives the user input and enables a suitable interaction mechanism between user and mobile application. It acts as a major driving force for a better user experience, contributing to user satisfaction. Moreover, it aids in developing smarter mobile devices by allowing them to identify and comprehend their usage environment to respond proactively and intelligently [21].

It is critical for app developers and businesses to perform a thorough comparative study of current applications with the existing work [19,31,32]. Developing a Graphical User Interface (GUI) of any mobile application involves UI design, wireframing, prototyping, and interactive design skills [33]. The UI design process gives insights as to what factors the developer can keep in mind to build a visually appealing design for mobile applications. The primary aim of the proposed survey is to provide necessary insights and suggestions for the UI/UX to the mobile application and UI/UX developers, thereby providing efficient designs and interactive modules for the mobile applications. It also provides information regarding the technologies that can assist the UI/UX development. An ineffective interface design not only causes user misery but also reduces user awareness and willingness to utilize it [23]. Hence, an efficient and likable user interface is needed to enhance the experience of a mobile application. The user experience is a result of the users’ internal condition, the attributes of the planned system (complexity, purpose, usability, functionality), and the context (or environment) in which the interaction occurs (organizational/social setting, activity relevance, usage readiness) [27].

3.1.3. Comparative Analysis between the UI and the UX

Both the UI and the UX have different perspectives in the mobile application domain, yet they work in parallel in optimizing the mobile application interfaces. Both are equally required for creating an interactive user-preferred mobile application’s front-end. Moreover, there is a close relationship between aesthetics and the system’s usability. The aesthetics are about giving the interface a sense of individuality, whereas usability gives the users some familiarity with some ease of use. System users often judge a mobile application by its aesthetics rather than its functionality. Hence, aesthetics play a crucial role in HCI design, thereby affecting users while experiencing their interaction with computerized systems [34] (here mobile applications). UI modeling [35] includes the establishment of information bases that explain different components (example: the presentation, the dialog, the platform, the task structure, and the context). These knowledge bases may be examined further to automatically provide a usable UI that meets the needs of each context of use [36]. However, the UX is an equally important part of mobile applications since it gives the ease to the users to train the human mind for getting accustomed to the product.

3.1.4. Designing Mobile Applications

The designing of any product essentially requires a thorough understanding of the people and the context it is to be designed for [28]. Therefore, ask the following questions before designing the interface for mobile applications. This helps in determining the flow and direction of the mobile application to be developed.

• What is the real-world application for which the mobile application interface is going to be developed?
• How will the mobile application interface help the considered real-world application?
• Who are the end users of the developed mobile application?
• How will the mobile application be managed once it is deployed on the Internet?

Designing and developing any mobile application involves multiple sequential steps to be followed for a successful outcome. The steps are briefly mentioned as follows.

• Identify the target audience.
• Research (includes reviewing existing apps with similar purposes).
• Decide the main functionalities of the mobile application.
• Decide the sequence of mobile interfaces.
• Create storyboards, wireframes, and sitemaps.
• Develop interface designs and prototyping.
• Implement UI designs into the source code.
• Capture metrics to know user behaviour.
• Beta user testing.
• Improve the UI/UX design and different mobile application functionalities.

In terms of scale and visual attention, it is important to give the following items priority.

• Content area.
• Branding.
• Levels of navigation or functionality.

Tools such as Zeplin and InVision Inspect work well for communicating designs because they take care of integrals such as spacing, style guides, fonts, user experience flow, and integrating every design component. StoryDroid is a useful tool to assist in application development. It enables several potential applications such as UI design recommendation [33].

3.2. Elements of the UI

Fabricating a UI is a design-centric process where mobile users’ content type and display modalities often vary during mobile operations. Users have control over multiple content display characteristics based on various factors, for instance, place, time, situation, interest level, and cost [24]. As per the survey results, Figure 4 represents the major factors affecting mobile application designs.

3.2.1. Iconography

Iconography is all about the icons used in mobile applications which can be logos or any visual images used to display a clickable/non-clickable button, which create a huge impact on users. They are responsible for the mobile application’s first impression on the users. The mobile application logo is a subtle indication of what it does. Creating icons that represent genuine perceptions of events or activities makes the system more interesting, engaging and involving local users [22]. Therefore, it is important to transform information into relevant keywords and design icons in a way that is easily understandable by the mobile users [22]. Some icons have more than one meaning, which may be synonymous with the actual meaning [22]. Hence, ensuring the correct interpretation of the icons’ use is non-trivial. Age and gender also have a notable role in the process of designing icons for mobile devices [37].

3.2.2. Typography

Font style, size, and decorations of any mobile application play a subtle role in shaping the mental perception of the users. Choosing the appropriate font is determined by the context and the target audience. According to the mood and age of the target audience, the correct typeface and most readable font size have to be chosen. For example, an application for connecting with employers around the globe cannot have stylish or elegant font styles. It needs to be quite formal and straightforward.

3.2.3. Shapes and Placements

The various shapes, sizes, and placement on the screen create a memorable visual impact on the human mind. Unfortunately, many mobile platforms have small-sized displays with low-resolution. The amount of display size needed for a UI design depends on the size of the actual interactors, the arrangement of the window interactors, and the distribution of interactors between multiple windows [36]. According to all these factors, the appropriate choice of lines, objects, padding, margins, spacing, and so on are to be decided.

The various shapes, sizes, and placement on the screen create a soothing visual impact on the human mind. According to Gestalt Theory [38], images include positive and negative space in a figure–ground relationship. The element of duality while maintaining a clean and clutter-free design is equally important. Hence, maintaining lesser chaos and providing more apparent choices is preferred. The way the users hold their mobile phones and what part of the screen their eyes get drawn to also play a considerate role. Fingers directly interacting with the screen, that is, haptics, create the necessity for motion and require a fluid relationship between the various states of any screen. If the same element appears on more than one screen, then to maintain consistency, the same scale and the same place of the element must be ensured. In addition, buttons with similar functionality but different states should be visibly similar enough so that the user does not have difficulty identifying the similarity between them. A few points that need to be addressed while selecting icons, shapes, colour, spacing, and other elements of a UI/UX design.

• Categorize the users and mobile phones based on their preferences and needs.
• Keep the clickable area large enough for comfortable use.
• Do not let the user lose focus due to too many focal points. Maintain center of attraction by preferably keeping it in the most viewed region of the screen (major center).
• Ensure the layout, placements, and sizing do not vary too much when switched between landscape and portrait mode of mobile phone.
• Show what is necessary. Items of less priority can be hidden and made accessible only when called for.

3.2.4. Images

The type of images, their colour scheme, and the way they are used in an application determine the main focus of any mobile application. The dominant discourse about the growth of the mobile Internet and app-centered media uses the symbol of freedom, empowerment, and autonomy for app users and producers [39]. A picture says much more than words and in less time. Furthermore, users might not go through the entire written content of mobile applications, but they surely go through most images in the application. The relevance and appropriate usage of images (stationary/moving) positively impact users’ minds, capturing their attention and interaction with the mobile application interface. Selecting the suitable size images, along with the number of images to be fitted on a screen of a mobile device, needs to be efficiently analysed and discussed between mobile application and UI/UX developers.

3.2.5. Colour Theory

Every colour is attached to its meaning and relevance. The user’s psychology on colours significantly impacts their perception of the mobile screen. Colour theory tells which colours to use, when, and how to use them. The appropriate colour in the proper place on a screen matters. A proper balance between hue (origin of the colour seen), value (degree of light and darkness), and intensity (a measure of brightness/dullness of colour) are significant for a beautiful colour play in any mobile application development. Furthermore, the choice of the colour palette depends on the target audience, their age, gender, and context. Steps to choose colour scheme:

• Choose a relevant image that matches with the context of the mobile application.
• Create a three-value sketch that depends on colour, space, form, and line.
• Choose a colour scheme from minimalist muted colour palettes that has a mixture of high contrast white colour instead of dark colours.
• Balance between cool, warm, and neutral shades of colour as suitable for the target audience.
• Maintain the colour scheme consistently throughout the application.

Currently, the fashion of monochromatic colour schemes has gained popularity; hence, it is difficult to select a suitable colour for the mobile application because they all look similar and show a minimal change while using it in the mobile design. Moreover, mobile applications have a rising trend for dark mode themes over the normal light mode. The major reason behind this is thought to be the less stress caused to the human eye, especially when in low-light surroundings. In addition, it improves the battery life of mobile devices having Organic Light-Emitting Diode (OLED), the most commonly used screen for mobile phone displays. [40]. Furthermore, dark mode colour schemes significantly increase visual acuity, reduce visual exhaustion, and are generally favored, particularly in physical environments with limited light and complex backgrounds [41,42].

3.2.6. Animation

Animations are the UI/UX design components that provide a sense of interaction between different shapes and objects of the real world. This improves the application’s user experience by creating incredible and lively creatures in the mobile application that assist the mobile user while interacting with the complex mobile interface. Additionally, it helps in smart interactions and paves the way for usability and user satisfaction.

3.3. Elements of the UX

Fabricating the UX is a user-centric process. The real underlying motivations for the use of technology are insight, pleasure, and social exchange. Emotions and impressions are the real effects of the UI/UX in the development of an interactive mobile application [28]. The UX is highly beneficial in verifying commands, keywords, and icons. The user and the community’s language, cognition, and social interpretations should be considered while building useful mobile apps [22]. Figure 5 represents the overall idea of UX design [27].

Golden rule is that a good user experience is a result of satisfying human needs for independence, competence, excitement (self-oriented), relatedness, and popularity (others-oriented) through interaction with a product or service (hedonic quality: stimulation, identification, and evocation). Users’ mental psychology and thinking are equally important factors in determining the appropriate UX for mobile applications. In addition, design thinking is integral to designing a UI for an optimum UX. It comprises the stages empathize, define, ideate, prototype, and test [11].

The user experience assessment, known as the User Experience Questionnaire (UEQ) [43], can be used to evaluate the UX. The QUIS surveys are used to measure the users’ overall satisfaction with the suggested approach [15]. The UEQ enables a quick evaluation of the UX by asking users to share their feelings, impressions, and attitudes after using a product. It assesses both traditional usability and user experience. It has been used by various companies to evaluate their products and has been believed to be a good measure of evaluation [15].

3.3.1. Goal Fulfillment

The UX originated from the do-goals and be-goals mentioned in Ref. [35]. The achievement of be-goals can influence a mobile developer to create more interactive mobile design interfaces. However, lack of usability may impede the achievement of active be-goals; thus, to achieve effective be-goals, one must adapt independence, knowledge, connection to others, inspiration, and popularity through the use of technology [28]. All objectives of be-goals must be completed while keeping the target audience in mind. From a design perspective, a highly interactive product should support the accomplishment of do-goals; nevertheless, without a consistent proposition of hedonic quality (the product’s perceived potential to service the achievement of be-goals), a product stays dull. All this revolves around improvising the comfort and ease of the end user. Hence, their emotions and psychological state play a crucial role in fabricating the UX of any mobile application. Therefore, it is essential to consider and understand the importance of an effective system for a broad spectrum of UI/UX design processes, such as human decision making or subjective well-being [27,44].

3.3.2. Usability and Ergonomics

The different features of the International Organization for Standardization (ISO), such as stability, learnability, understandability, and operability, denote how user friendly a mobile application is. Furthermore, the Nielson model in [45] takes the ISO model one step ahead by incorporating more features, such as taking into account efficiency, satisfaction, learnability, memorability, and errors, to improvise the UI/UX design patterns. Then, People At the Centre of Mobile Application Development (PACMAD) is proposed by [46] that not only includes the attributes of both the ISO and the Neilson model but also takes into account the cognitive load, hence providing a holistic approach for usability testing. Furthermore, obtaining useful feedback and insights from unacquainted users as early as possible helps the developer to improve the usability of the mobile application quickly. The simplest and most effective approach to enhance usability is to conduct interface evaluations that include three essential components, such as users, their activities, feedback, and user evaluation [23]. Nielsen’s usability heuristic is one of the most widely used usability evaluation methods [47]. Heuristic evaluation is a usability inspection method that identifies the usability problems in a UI design. It examines the interface and evaluates its compliance with recognized usability principles, i.e., heuristics. A major objective of heuristic evaluation is to identify various design-related problems in a UI. Usability testing techniques are a basic system with 10 scales that provide a glimpse of the overall aim of usability [48]. The System Usability Scale (SUS), which employs a Likert scale questionnaire, is used to assess the system’s grade usability [11,17].

According to a study mentioned in [49], pleasant emotions and memories are measured by behavioural intentions and appear to be a good predictor of product design performance. As the popularity of mobile application design grew, high usability became connected with positive feelings associated with the UX, and its benefits on behavioural intentions increased. However, the impact of the UX has remained consistent throughout time [49]. All the user-centered research and evaluation methodologies aim to supplement current product quality models with non-instrumental features to build a more accurate and integrated HCI application [27].

3.3.3. Utility Satisfaction and User Control

According to R. Fox, privacy, ethical issues, and hidden app costs have the highest negative impact on app ratings, affecting the mobile application reviews [19]. This indicates the importance of gaining user trust and meeting expectations in the application. Catering to the users’ needs to fulfill the purpose of a mobile application is essential. Mobile users often want commands based on mood, personal preferences, mobility circumstances, and cost factors over different media proportions such as audio, video, animations, graphics, and text. Various media combinations must be delivered with the same material to fit other versatility conditions [24] and hence improving user satisfaction. Questions to be kept in mind for inspection (as a developer) are as follows.

• How well does the application interface assist the users?
• Is the application responsive enough?
• Is there any redundancy of screens or functions, which might put the users into any dilemma?
• In case of an error, how does the mobile application respond? Does the application give satisfactory help when needed?
• How easy is it for the users to navigate between the screens?

A logical and predictable flow enhances user satisfaction. Constant feedback builds a sense of trust in users’ minds. The best way to do this is to put oneself into the users’ shoes, getting the experiential perspective. Reinforce the experience and engagement of interactive products rather than just the content [27]. Some unexpected behaviour or unforeseen condition should not boggle the user. The application should be able to handle this kind of situation gracefully. The more user diversity is acknowledged, the better the mobile application will be. Taking care of any limitation is also a plus; for example, to accommodate users with weak eyesight, the solution is to provide larger fonts/buttons or a tool tip wherever necessary. In addition, some standard conventions to which every user is accustomed (such as navigation bar, tab-bar, and app drawer) should be utilized for users’ ease of use.

Remember: ’Utility satisfaction and user control’ and ’Ergonomics and usability’ are interwoven parameters that go hand-in-hand with each other. They have an impact on each other.

3.3.4. Language

Appropriate selection of words and sentences (and their proper framing) plays a crucial role in mobile application development. Even if a warning/error message has to be displayed, it has to be framed in a subtle/soft tone not to disrespect any of the users. The way any text is conveyed to the users, the tone, the choice of words, everything matters a lot. All of these decisions revolve around the target audience of the mobile application; for instance, for designing a mobile application having a target audience of children, the wording and tone of the application should be child-friendly, devoid of any abusive language. Using Semantic Differentials (SD) as the key methodology for obtaining the consumer’s Kansei (interpreting and converting technology of customer’s feeling and image for a product into design cues) [50] can be of great help for the relevant choice of language according to the user base.

Through contemporary mobile technologies, global languages can exert more artful pressure, impacting multilingual consumers’ attitudes toward global languages by offering a more enjoyable and efficient user experience [51]. This might not hinder developing mobile applications having a target audience mainly speaking global languages. However, when the target audience speaks a variety of languages/vernaculars, the ease of use for such users will be hindered by the language used for communication by the mobile application. Hence, using vernacular languages as an option can enhance the usability of mobile applications. Research suggests a forward-looking model for developing mobile minority language interfaces evoking a deeper analysis of user interaction in the minority languages, especially for mobile social applications. Social mobile application developers should grasp how software-based keyboards and predictive text algorithms can accommodate simultaneous languages, separate dictionaries, and numerous predictive text corrections from inside the same interface [51]. In addition, with the help of a tool tip, even the needs of different abilities can be addressed.

3.3.5. Minimalism

According to E.F. Schumacher, “Any intelligent fool can make things bigger and more complex. It takes a touch of genius and a lot of courage—to move in the opposite direction”. The content of a mobile application should be clear and concise. For a simple yet effective mobile interface, the concept of minimalism should be followed. Minimalism is all about saying "much" in "less", i.e., to convey something, use words or visuals only when and where required. Every element of a UI is not necessary to be implemented to have an effective UX. Using what is necessary is enough for effective communication. Simplicity serves a purpose. The beauty of machines is created by combining power and simplicity [52]. Do not bombard the user with too much information. The human mind cannot remember too much information. Hence, the design of the mobile application must be planned accordingly. “Simplicity is the ultimate sophistication” is the ultimate quote that is adapted by many UI/UX developers to design interactive mobile interfaces. The Bauhaus school of design adopted the motto “form follows function” and tried to remove excessive and unnecessary decoration [52].

Minimalism ensures a smooth and mind-easing user experience, simplifying things and staying focused on the necessary information. Figure 6 represents the four notions of minimalism, concentrating on the interface’s purpose, structure, design, and composition [52]. The focus should be given to reducing the complexity without compromising the application’s functionality. Minimalism helps the user feel in control [52]. In a nutshell: from the design point of view, "Simple is the new style statement". However, remember that minimalism is not a compulsion to follow. It is the user audience and their choices that decide which approach to pursue: minimalistic or maximalistic.

4. Survey: Result and Analysis

In this section, we have performed a pilot survey analysis using the survey methodology mentioned below and developed an extensive result as shown below.

Table 2. Analysed results of survey.

Parameter	Categories	Logo	Interface	Mode	Searching	Notification	Reviews	Vernacular
Gender	Male	Tend to be important	Prefer minimal designs	Does not matter much. Equally prefer both	Excessive searching is problematic	Indecisive	They do matter	Might be useful
	Female	Tend to be slightly less important	Prefer minimal designs	Prefer light mode over dark	Excessive searching is problematic	Indecisive	Indecisive	Might be useful
Age	11-20	Tend to be important	Tend to prefer minimal designs	Prefer dark mode over light	Excessive searching is problematic	Useful, but excessively frequent notifications are annoying, rather they should be in a limited amount	Tend to matter	Might be useful
	21–30	Tend to be important	Tend to prefer minimal designs	Tend to prefer dark mode	Excessive searching is problematic	Annoying	Matter	Might be useful
	31–40	Not much important	Prefer minimal designs	Prefer dark mode over light	Tend to believe much searching as a problem	Tend to believe notifications to be annoying	They do matter	Might be useful
	41–50	Not much important	Prefer minimal designs	Light	Excessive searching is problematic	Annoying	Tend to matter	Tend to be useful
	51–60	Tend to be less important	Tend to prefer minimal designs	Light	Excessive searching is problematic	Tend to believe notifications to be annoying	Tend to matter	Tend to be useful
	Above 60	Tend to be slightly less important	Prefer minimal designs	Prefer dark mode over light	Indecisive	Useful	Indecisive	Useful
Description	Programmer	Tend to be important	Prefer minimal designs	Prefer light mode over dark	Excessive searching is problematic	Excessively frequent notifications are annoying, rather they should be in a limited amount	They do matter	Might be useful
	General user	Indecisive	Prefer minimal designs	Prefer dark mode over light	Excessive searching is problematic	Indecisive	They do matter	Might be useful
	UI/UX Designer	Plays a very important role	Prefer minimal designs	Does not matter much	Excessive searching is problematic	Useful	They do matter	Might be useful

represents the conclusion of the data received in our pilot survey.

4.1. Survey: Methodology

In our survey methodology, we surveyed 201-odd participants, including programmers, UI/UX designers, and general users. We present the layout of the demographic decomposition of survey respondents for description of age range decomposition and gender decomposition respectively.

• For age range decomposition, we considered 54% from the age group of 11–20 years old, 11% 20–30 years old, 4.5% 30–40 years old, 20% 40–50 years old, 8.5% 50–60 years old, and 2% over 60 years old.
• For gender decomposition, we considered 58.7% male and 41.3% female users.
• For description decomposition, we considered 71.1% as a general user, 16.4% as a programmer, 10.9% as a UI/UX designer, 1% from general user and UI/UX category, and 0.5% from programmer and the UI/UX category.

We believe that the above parameters have a big role in determining the context of mobile applications. Building applications that cater to the right audience, fulfilling their needs and expectations is a must. Hence, obtaining their views on existing mobile applications is important. An online survey (form) best fits our needs for gathering data regarding mobile applications. Understanding the technological and emotional expectations and pains of people, using the existing technology seemed to be the correct way to do so. Table 2 shows the overall result of the proposed survey. Instead of a pre-existing public dataset available, which may or may not cater to our goals, we designed a custom survey for the benefit of application developers and junior designers in the mobile application industry. Both qualitative and quantitative data were obtained from the participants. The questions asked revolve around the following:

• First impression - The effect of name, logo, and reviews of the application (play store or verbal).
• Aesthetics/Beauty - Impact of user-friendliness, minimalism, colours, icons and shapes, placement of elements, font style, language, animations, and mode of application (dark or light).
• User Interaction - Impact of excessive searching/scrolling in reaching a particular screen and the need for vernacular language.

Based on their age, gender, and description, their preferences and perceptions regarding elements of the UI/UX were noted. From a UI perspective, Figure 4 depicts the percentage breakdown of ratings (on a scale of 0 through 5) and the importance the survey respondents give to the different aspects: animation, language, font, placement, icons and shapes, and colours.

From a UX perspective, the elements taken into consideration here are the importance of a logo, the (simplicity of) interface preferred, mode (theme) preferred, the presence of searching (clicks required to reach a particular screen), their perception of notifications/response, reviews on the app store, and vernacular language as a mode of communication with the users.

4.2. Result and Analysis

Figure 4 shows that the participants have given an overall rating of at least 3 out of 5 for each UI aspect, which means that all the aspects are important. Out of all the aspects, if there is a clear distinction to be made, the graph shows that language has been given the highest importance and animation given the least importance. Table 2 represents the conclusion of the data received. Moreover,

Table 3. Parametric perception data from survey: Males.

Description	Age Group	Total	Logo			Interface			Mode			Searching			Notifications			Reviews			Vernacular
			Yes	No	Maybe	Minimal	Eyecatching	Both	Dark	Light	Both	Excessive	Manageable	Notsure	Useful	Annoying	Limited	Matter	Don’t matter	Maybe	Yes	No	Maybe
Programmer	11–20	19	11	4	4	8	5	4	5	0	2	15	2	2	4	4	7	11	4	1	4	0	3
	21–30	4	1	1	2	2	0	2	1	1	0	2	0	2	0	3	0	3	0	0	1	1	0
	41–50	2	2	0	0	2	0	0	0	2	0	2	0	0	0	2	0	2	0	0	0	2	0
General user	11–20	44	18	10	14	16	6	12	11	7	2	26	4	11	13	10	9	25	6	1	12	2	16
	21–30	13	5	2	6	7	0	5	7	2	1	9	3	1	1	6	4	7	4	0	6	2	1
	31–40	1	0	1	0	1	0	0	1	0	0	1	0	0	0	0	1	0	0	1	0	1	0
	41–50	9	2	5	2	8	1	0	1	8	0	5	1	3	0	5	3	7	2	0	5	2	2
	51–60	16	7	9	0	10	4	2	0	6	2	10	2	4	3	8	3	12	4	0	7	1	6
	Above 60	3	2	1	0	3	0	0	0	1	2	1	0	2	2	0	1	2	1	0	2	1	0
UI/UX Designer	11–20	7	4	2	1	4	0	2	0	0	0	5	0	1	4	0	1	4	1	0	0	0	0
	21–30	2	2	0	0	1	0	1	0	0	0	1	0	1	0	1	0	0	1	0	0	0	0
	41–50	3	1	2	0	3	0	0	0	0	3	3	0	0	0	1	2	3	0	0	1	2	0

and

Table 4. Parametric perception data from survey: Females.

Description	Age Group	Total	Logo			Interface			Mode			Searching			Notifications			Reviews			Vernacular
			Yes	No	Maybe	Minimal	Eyecatching	Both	Dark	Light	Both	Excessive	Manageable	Notsure	Useful	Annoying	Limited	Matter	Don’t Matter	Maybe	Yes	No	Maybe
Programmer	11–20	8	1	2	5	3	1	3	2	1	0	5	1	2	0	3	2	5	1	0	1	0	2
	21–30	1	1	0	0	1	0	0	1	0	0	1	0	0	1	0	0	1	0	0	1	0	0
	41–50	1	0	0	1	0	0	1	0	1	0	0	1	0	0	1	0	0	1	0	0	0	1
General user	11–20	28	12	9	7	9	10	8	10	4	0	13	6	9	14	3	6	4	15	1	9	1	5
	21–30	2	1	0	1	1	0	1	0	0	0	1	0	1	0	1	0	1	0	0	0	0	0
	31–40	7	1	3	3	6	1	0	5	2	0	3	2	2	1	4	1	5	2	0	2	0	5
	41–50	23	4	14	5	11	7	5	2	18	0	16	0	7	6	13	2	10	11	1	5	3	13
	51–60	2	0	1	1	2	0	0	0	2	0	1	0	1	1	1	0	2	0	0	0	0	2
	Above 60	2	0	2	0	0	0	0	2	0	0	0	1	1	0	0	0	0	1	0	2	0	0
UI/UX Designer	11–20	5	4	0	1	1	2	2	2	0	0	3	2	0	4	0	0	4	1	0	0	0	2
	21–30	1	0	1	0	0	1	0	0	0	1	0	1	0	0	1	0	1	0	0	0	0	1
	31–40	1	1	0	0	1	0	0	0	1	0	1	0	0	1	0	0	1	0	0	1	0	0
	41–50	3	1	2	0	3	0	0	1	1	0	1	0	2	1	0	2	2	1	0	1	0	2
	Total	84	26	34	24	38	22	20	25	30	1	45	14	25	29	27	13	36	33	2	22	4	33

represent the data as collected from the respondents. After processing the raw data, observations were made according to their respective percentages.

From the numeric figures in the tables from the survey, it is clearly noticeable that the planning, designing, and further development of a UI and the UX highly depends on the users’ preferences and involvement, which in turn depends on various factors such as age, gender, or mindset based on their technical background. Hence, a careful study of every factor is essential for building a seamless mobile application.

5. Conclusions

In this paper, we discussed the preferences and perceptions of a heterogeneous group of concerned people. These preferences would serve as a reference to mobile application developers, which gives them useful insights. Our proposed approach would help mobile application developers and designers to focus on particular UI/UX problems of mobile applications per their relevancy. A comparative analysis of the various UI and UX factors that determine a mobile application interface is presented in this paper. UI and UX are the two lifelines which play a crucial role in designing and developing various mobile applications. Hence, developers should consider all the aforementioned points when developing the application. The current generation demands a smooth interaction with their devices through mobile applications. The look (UI) of an application helps the user engage with it by making it more appealing to them, while the functionality (UX) helps create a positive impression on the users’ minds for long-term interaction and satisfaction. An appropriate balance between these two entities is a necessity in mobile application development.