Trust Components: An Analysis in The Development of Type 2 Diabetic Mellitus Mobile Application

Abstract

Trust in information and communication technology devices is an important factor, considering the role of technology in carrying out supporting tasks in everyday human activities. The level of trust in technology will influence its application and adoption. Recognizing the importance of trust in technology, researchers in this study will examine trust components for the development of a type 2 diabetes mobile application. The results of this study resulted in three major focuses, namely the application design (consisting of architecture), UI design, and evaluation of trust factors of the application: functionality, ease of use, usefulness, security and privacy, and cost. This analysis of trust components will be useful for the application or adoption by users of a type 2 diabetes mellitus mobile application so that users will trust the application both in terms of functionality and the generated information.

1. Introduction

1.1. Mobile Health Application for Diabetes Mellitus

Mobile health applications are software tools that help users monitor their health conditions via smartphones and tablets [1]. Their functionality ranges from simple diaries, medication reminders, and tracking health progress to more complex programs certified as medical devices by health authorities. Currently, mobile health applications with a large number of users have a high potential for improving healthcare [2]. The reliability of these applications remains in doubt, limiting their widespread adoption [3]. Extensive research on trust in technology and the role of user trust in the selection of various information technology (IT) artifacts have yet to be conducted [4].

Diabetes mellitus is a genetically and clinically heterogeneous metabolic disorder characterized by carbohydrate tolerance loss [5]. Diabetes mellitus is clinically characterized by fasting and postprandial hyperglycemia, atherosclerosis, and microangiopathic vascular disease [6].

Diabetes mellitus is classified into two types: type 1 and type 2 diabetes. Type 1 diabetes is characterized by the pancreas, the body’s insulin factory, being unable or less able to produce insulin [7]. As a result, the body’s insulin is lacking or not present at all, and sugar accumulates in the blood circulation because it cannot be transported into cells [8]. Type 2 diabetes mellitus (T2DM) is the most common type [9]. The pancreas can still produce insulin in type 2 diabetes, but the quality of the insulin is poor, and it cannot properly function, causing blood glucose levels to rise [10]. Patients with this type of diabetes usually do not need additional insulin injections in their treatment but do need drugs that work to improve insulin function, lower glucose, improve sugar processing in the liver, and perform several alternative treatments for support [11]. Age, sex, family history, physical activity, and eating habits are the risk factors that have the greatest association with the incidence of type 2 diabetes mellitus (T2DM) among the many factors that cause diabetes mellitus [12].

All types of diabetes can cause many complications in the body and increase the risk of premature death. Heart attack, kidney failure, stroke, leg amputation, vision loss, and nerve damage are all possible complications. Type 2 diabetes mellitus (T2DM) is a chronic disease that requires ongoing therapy and patient education to prevent acute complications and lower the risk of long-term complications [13].

Type 2 diabetes mellitus (T2DM) problems can be overcome in various ways, including pharmacologically and non-pharmacologically. Non-pharmacological therapy includes lifestyle changes by adjusting diet (medical nutrition therapy), therapy using fruit juice, increasing physical activity, and education on various problems related to diabetes, all of which are continuously carried out. Pharmacological therapy includes oral anti-diabetic administration and insulin injections. Pharmacological therapy should be used in conjunction with non-pharmacological therapy [14].

1.2. Usability Test

Usability has a word for “usable”, which is defined as being useful. To be considered good, something must minimize failure while also providing satisfaction and benefits to application users [15]. Usability is the ease of using something. In this case, it is intended that the developed application be simple to use and testing be conducted to determine the success of the developed application by focusing on ease, effectiveness, efficiency, and satisfaction of users [16].

Usability is a factor that determines whether an application is good or not. There are five main components of usability [17]. The five components are learnability (easiness to learn), efficiency (efficiency), memorability (ease for users to remember), errors (error rate), and satisfaction (satisfaction) [18].

Usability testing is a process that involves people as test participants, representing targets, to evaluate the extent to which a product meets usability criteria [19]. Usability testing can be performed by interviewing or giving questionnaires to users [20]. In testing the user groups, it is recommended to use 3–4 users from each category if there are two groups. However, if there are three or more groups of users, then use three users from each category for the usability level measurement listed in

Table 1. Usability Level Measurement.

No.	Usability Level Measurement
	Level	Description
1	Learnability	It is defined as the speed with which the user can use the system, the ease of use in the performance of a function, and the wishes of the user.
2	Efficiency	It is defined as a resource instrument that has a function to achieve better goals.
3	Memorability	Users are tested to see how long they can remember using the application.
4	Errors and security	How many problems are caused by errors that are inconsistent with what users expect from the system?
5	Satisfaction	The application’s freedom of expression and user comfort are both subjective measures of the user’s perception of the system.

[21].

1.3. Trust in the Mobile Application

The idea of competence is that an agent will safely, dependably, and consistently operate in a particular situation, which underlines how crucial trust is to the deployment of any online ecosystem. That is, whether an entity decides to do business with another firm is heavily influenced by trust in the original firm. The authors argue that, before using or providing services in an electronic market, both the consumers and providers must have trust in one another. If there is no mutual trust between them, then resources will not be fully shared, and there may be a lot of fraudulent transactions. Such a situation would be detrimental to honest buyers and sellers, preventing them from taking advantage of the benefits of the online world [22].

Trust, as it is in the online system, is critical to the success of mobile applications. Customers must constantly choose which mobile apps to download and/or use because there are hundreds of thousands of them available in application stores. When several mobile apps with comparable functionalities begin to appear in application stores, the decision becomes even more difficult because users must choose the most reliable application. Customers will always prefer to download and use a mobile app that is useful, dependable, and of high quality. However, it can be difficult to choose a mobile app that is thus practical, trustworthy, and high quality. This is evident from the numerous comments left by users who downloaded poor-quality mobile applications and expressed their frustration with them in the application shops. Therefore, it is essential to establish early confidence in mobile apps before users download and use them [23].

From a security and privacy standpoint, the emergence of mobile apps poses additional threats to the confidentiality of information and data. There have been several instances where mobile apps have grabbed and mined private information from users, including address books, photographs, and more. Such occurrences blatantly expose the invasion of the client’s privacy and further harm the consumers. Unfortunately, it reveals that more than half of the popular mobile applications for Android and iOS under consideration send user data to third-party servers. Aside from the issue of individual privacy, an increasing number of organizations and businesses are also opposed to their employees using mobile devices [24]. They are extremely concerned about the possibility of mobile apps accessing and gathering sensitive and important company documents (e.g., through business emails on mobile devices).

Installing security measures and policies can reduce the risk of sensitive business information being leaked to the public, but these must be supplemented and improved by the use of trust measurement. The majority of security experts agree that the best strategy for reducing the risk of document leakage in mobile apps is to prevent applications from being installed in the first place. However, such a strategy could not be advantageous for both employees and enterprises, especially in light of the fact that mobile apps increase employee productivity and benefit companies. Therefore, there are only two options left for protecting crucial corporate data: teach staff how to choose legitimate mobile apps and provide them tools for evaluating the reliability of mobile apps before installing and using them. Measuring trust in mobile apps is critical as the primary and additional layer of security and privacy protection. Trust also improves security by better-securing resources and information [25].

1.4. Previous Research

Initially, the development of an Android mobile application was focused on controlling type 2 diabetes. At this point, the research team had 20 people, ten with diabetes and ten without, participate in the use of diabetes mobile applications with supporting hardware, such as a wearable band, glucose meter, and treadmill [26]. The results of the initial research are used as reference material for the development of the second stage. At this stage, the researchers evaluate some of the functionality and accessibility of the application by conducting tests involving 40 people, consisting of twenty with diabetes and twenty without diabetes. The results of the second stage of research conclude that there is a need for changes and adaptation of applications for users, especially related to user registration for applications, as well as glucometer and wearable band (smartwatch) connectivity with various versions [27]. Previous researchers have conducted preliminary research through two previous studies, which are shown in

Table 2. Previous Research.

No.	Research
	Title	Year	Publisher
1	“Therapeutic Exercise Platform for Type 2 Diabetic Mellitus” [26]	2021	Journal of Electronics, MDPI
2	“Self-Care IoT Platform for Diabetic Mellitus” [27]	2021	Journal of Applied Sciences, MDPI

.

2. Analysis

2.1. Mobile Application in Healthcare

Smartphone users continue to increase as mobile phones become more sophisticated, efficient, and portable. The use of smartphones has become an important item and a lifestyle in society. A mobile application is one that enables mobility through the use of equipment, such as a cell phone (mobile phone), a PDA (personal digital assistant), or a smartphone [28]. Mobile applications can wirelessly access and use a web application using a mobile device, where the data obtained is only in the form of text and does not require much bandwidth. The use of the mobile application only requires a mobile phone that is equipped with General Packet Radio Service (GPRS) facilities and its connection. There are several aspects that must be considered to build a mobile application, especially the hardware. In terms of bandwidth, the current network conditions have made it possible to obtain a large enough bandwidth for the cellular network [28].

Table 3. Application Classification in Healthcare.

No.	Application Classification
	Researcher	Classification	Description
1	B. D. A. Pititto	Disease prediction	A disease prediction application is an application that is used to help patients or application users find out the prediction of disease along with the overall results of the obtained diagnosis based on the symptoms felt. This application was developed using certain methods according to the scope of the case study (disease) to be analyzed by calculating all parameters related to the symptoms of the disease. The development of this disease prediction application is useful to help doctors and also provide recommendations to patients or users who have difficulty knowing the disease they are suffering from but only know the symptoms they feel.
2	J. H. Park	Clinical communication	A clinical communication application is the development of technology in the health sector that helps achieve a state or health status as a whole, both physically, mentally, and socially. This application focuses on communication-related health. The database in this application will store and process the existing data so that it can be useful for later use. Several clinical communication applications provide real-time communication services between patients and doctors to conduct health consultations. Doctors will collect information about the patient’s health status, or they can access a database to view the patient’s medical history.
3	Adu, U. H. Malabu	Medication	The lack of information about treatment and drugs is the basis for developing health applications in this field. If it is not handled properly, the patient or customer will self-regulate the drug therapy they receive, which will lead to an increase in cases of drug administration errors that are not in accordance with the patient’s needs. The medication health application focuses on education about drug information, assisting in health consultations on drug administration based on symptoms, and viewing the history of purchasing and using drugs stored in the database.
4	Lee, J.-H.	Exercise	Exercise health applications (also called health and fitness applications) are applications that can provide information to users without limitations of place or time and help them achieve their health and fitness targets. Some exercise applications provide features that are able to connect applications with other supporting devices to collect health information more comprehensively, for example, by connecting applications with treadmills, cycles, smartwatches, or other supporting devices.
5	R. K Więckowska	Nutrition	The nutrition application is an application that helps patients and users find out their nutritional needs and status by referring to nutrition and health sciences efficiently, cheaply, and accurately when each country has different nutritional guidelines. This is extremely useful because food consumption has an impact on a person’s nutritional status. Good nutritional status, also known as optimal nutritional status, occurs when the body receives and uses enough nutrients to support physical growth, brain development, workability, and overall health to the greatest extent possible. The nutrition application already has a nutritional value based on a calculated formula (nutritional standards). By accessing the database, the application can find specific numbers (foods or beverages) that will be or have been consumed.

summarizes the application classification in healthcare.

Several mobile-based applications in the healthcare sector have been developed with a variety of operating systems, depending on user needs, such as Android, iOS, Windows Mobile, Blackberry OS, and Symbian. Android is a mobile device software collection that includes an operating system, middleware, and the main mobile applications [29]. Android has four distinct features (

Table 4. Android Characteristics.

No.	Android Characteristics
	Characteristic	Description
1	Open source	Android is designed to be completely open, allowing any app to access any of the phone’s core functions, such as making calls, sending text messages, using the camera, and so on. To optimize the device’s memory and hardware resources, Android employs a specially designed virtual machine. Because Android is open source, it can be freely expanded to include newer, more advanced technologies as they become available. This platform will continue to evolve, allowing for the development of innovative mobile applications.
2	Accessibility	Android makes no distinction between the phone’s main application and third-party applications. All applications can be designed to have equal access to a phone’s capabilities to provide a diverse range of services and applications to users.
3	Reliability	Android removes barriers to developing new and innovative apps. A developer, for example, can combine web information with data on a person’s phone, such as the user’s contacts, calendar, or geographic location.
4	Easy to develop	Android provides a wide range of libraries and tools for developing better applications. Android includes a set of tools that can be used to help developers increase productivity when developing Google Inc. applications. Google has rebuilt Android from the ground up and made it open source, allowing developers to use it without paying Google for a license and build Android without restrictions. The Android Software Development Kit (SDK) includes the tools and Application Programming Interface (API) required to begin developing applications for the Android platform in Java.

) [30,31].

2.2. Telehealth

As a part of telehealth, telemedicine focuses on the therapeutic side, while telemedicine covers the prophylactic, preventive, and therapeutic aspects. One of the functions of telehealth and a major requirement for providing health services is patient monitoring and scheduling [32]. The coverage of telehealth, telemedicine, and electronic health (e-health), as well as telecare and m-health, is described by Totten AM et al. (

Table 5. Telehealth Operational Definition.

No.	Telehealth Operational Definition
	Objective	Description
1	Synchronous	Provides services or remote health services at the same time as consultations via video call (Zoom, Skype, etc.) or telephone
2	Asynchronous	Provides health services via emote/not concurrently (email or online chat consultation).
3	Mobile health	A mobile-based health service, such as health education and consultation, can be delivered through smartphones or mobile-based applications.
4	Virtual agent	Remote health service delivery through certain chatbots or applications that can help patients or users conduct 24 h health consultations
5	Artificial intelligence	Remote health services with artificial intelligence technology, such as being able to measure heart rate, make drug recommendations based on symptoms, and calculate or monitor sleep hours

) [33].

3. Research Methodology

3.1. Research Method

This study was carried out at Kangwon National University’s Circuit and System Design Laboratory with several systematic stages in order to produce research reports and products (a mobile application) that were in accordance with the objectives of the research implementation. The research method includes four stages (Figure 1), starting with system requirements, designing system architecture, developing a prototype, and implementing it.

3.2. Software Development Methodology

A “framework” is a software development method that is used to structure, plan, and control the process of developing an information system. Over the years, many different frameworks have been developed, each with its own set of strengths and weaknesses. The prototype model is suitable for exploring customer requirements and specifications in more detail, but it has a high risk of increasing project costs and time. The software development model used is a prototype model [34].

In developing this application, we use the prototype model as an approach to mobile application development. We undergo three stages: creating and revising the mockup, conducting customer test drives, and listening to customers. All steps in this prototype model were chosen because they are in accordance with the project being developed, which does not have many stages, and the parties or teams involved can also be maximized in the three existing stages (Figure 2). The details of each process are summarized in

Table 6. Application Development and Assessment.

No.	Application Development and Assessment
	Process	Description
1	Build/Revise mockup	The prototype model begins by gathering customer requirements for the software that will be created. At this stage, we researchers are gathering information about the needs of type 2 diabetes mellitus (T2DM) patients, which is poured in the form of features and services that monitor medication, food intake, exercise, and sleep.
2	The customer test drives the mockup	After listening to customer needs, a prototype program is created to give customers a better idea of what they truly want. The prototype program is typically an unfinished (but fully functional) program that simulates the software flow so that it appears to be completely finished. In this study, our researchers focused on four customer needs as functions or features in the application: medication monitoring, food intake monitoring, exercise monitoring, and sleep monitoring features.
2.1	Requirement analysis	The requirement analysis stage is characterized by an intense interaction between the system analysts and the system user community (end-users), during which the system development team demonstrates its expertise in order to gain user feedback and trust and obtain good participation. Because users may have had previous information system failures, it is difficult to persuade them to agree (being skeptical) about their information system requirements.
2.2	Design assessment form	Assessment in application development is an effort to obtain data or information from the processes and results that have been carried out. Before conducting an assessment, an assessment form is created, which includes several indicators to ensure that the information the users seek is accurate.
2.3	The customer uses the application	At this stage, the customer will use the mobile application that has been developed, where the application to be used is the latest updated version (version 2) with several changes from the previous version (version 1).
2.4	Assessment by the customer	The previous stage’s assessment form is distributed to customers in order to gather information about the application’s use on both the performance of version 1 and version 2 of the application.
2.5	Analyze and report	The assessment form that has been distributed will be collected and analyzed for data, and after that, it will be made into a report.
3	Listen to the customer	The customer or user evaluates this prototype program until specifications that match their wishes or needs are found. At this stage, the researcher will conduct a test involving 40 users who are participants (diabetic patients or non-patients) who are involved in using a mobile-based diabetes application.

.

4. System Design

4.1. User Interface

The user interface (UI) is the part of the experience with which the user interacts [35]. UI is not just about colors and shapes but about providing users with the right tools to achieve their goals. In addition, UI is more than just buttons, menus, and forms that the user must fill out. A “user interface” is used when the system and users can interact with each other through commands, such as using the content or entering data. The user interface is one of the most important aspects of application development because it is visible, audible, and touchable. At this point, the researchers have created (

Table 7. Design of the Application.

No.	Design of the Application
	Page	Mockup (Design)	User Interface (Implementation)
1	Login On the login page, the user will fill in data in the form of an ID and password (if you have previously registered), while for new users, the application provides services to register by filling in detailed data or automatically using a Google account.
2	Personal information Users are asked to enter information, such as their nickname, sex (male or female), date of birth, height, and weight, on the personal information page.
3	Home On the home page, the application briefly displays features that can be explored by users in the form of icon visualization, such as statistics to view the results of health data calculations, Bluetooth connections to devices, surveys, sugar levels, medicine, exercise, and a calendar.
4	Register IoT pack Users use the Register to IoT Pack page to connect applications to devices they own, such as wearable bands, glucometers, treadmills, and so on.
5	Monitoring medication The medication monitoring page enables users to view or control the medication intake schedule as recommended, or it can be entered manually by the user.
6	Monitoring food intake The food intake monitoring page allows users to directly control food intake by making direct adjustments at the specified time, which is divided into three parts: breakfast, lunch, and dinner.
7	Monitoring exercise The exercise monitoring page helps users see the exercise that has been completed. The results of the exercise are in the form of current speed, average speed, distance, and heart rate.
8	Monitoring sleep The sleep monitoring page is visualized in the form of charts and calendars to make it easier for users to see the results of the evaluation and monitoring of sleep. The user can see the total presentation as well as the average rest and sleep hours of the user.

) a user interface for the type 2 diabetes mellitus mobile application based on the appropriate needs.

4.2. Benefits of Application and Trustworthiness

In application development, there must be benefits that are expected to be the goal of developing the application. The following are the potential benefits of the type 2 diabetes mellitus mobile application.

Table 8. Potential Benefits of the Application.

No.	Benefits
1	Patients can accurately determine the level of risk of type 2 diabetes mellitus
2	Increase patient capacity for self-management of type 2 diabetes mellitus
3	Facilitates the decision-making process for optimal insulin dosage
4	Help maintain and manage a healthy lifestyle
5	Doctors will be more helpful in diagnosing type 2 diabetes mellitus and its complications
6	Nutritionists will be more helpful in determining the daily menu and physical exercise for people with type 2 diabetes mellitus
7	Improve communication between patients and healthcare professionals

summarizes the potential benefits of the application.

Trust components in the development of an application are an important factor (

Table 9. Trust Components in Mobile Application Development.

No.	Trust Components	Description
1	Convenience	Basically, users use the application because its functionality fulfills their needs. The development of this diabetes mobile application was made with the aim of helping users meet their needs and providing users with an easy and efficient way to find out their needs related to diabetes treatment/prevention. Convenience, in this case, includes several parts, namely: - Access to mobile applications This is marked by the development of Android applications that can be run online/offline. Easy access anywhere and anytime. - Searching applications The convenience of searching for applications is provided to users by providing access to download applications for free which can be found through the Playstore or other online platforms. - Decision The convenience of the decision is given to the user through the provision of various features that can complement the needs of the user. This shows that the development team provides the flexibility of access to users to decide what services they want to use according to user needs. - Using the application Users will be able to understand the features available in the mobile application thanks to the user-friendly user interface design. This is evident in several designs on the mobile application page that makes use of icons to help users understand the available features.
2	Attractiveness	Diabetes mobile application development has an attraction that can make customers want to use this application in the form of: - User interface design Landing page elements in diabetes mobile app development; - Price Users do not need to spend money to buy applications because the applications provided are free to install on their mobile devices; - Accessibility Users can access and monitor personal information contained in the history of the diabetes mobile application; - Connectivity The developed application can be connected to a glucometer and other supporting devices, such as a wearable band with a Bluetooth connection.
3	Simplicity	Simplicity is an important indicator that acts as one of the benefits of diabetes mobile applications, including: - Easy to remember The design of the application interface makes it easy for users to remember every feature available in the diabetes mobile application; - Directional Users can easily navigate the application. The application can guide users step by step using menus available in the application, namely through procedures that are easy to learn and understand; - Continuity Consistency is needed in an application. The point is so that users, especially novice users, can still recognize that the page they are viewing is still within the scope or has a relationship with the application being used.
4	Information quality	The quality of information is one of the important advantages for users, especially diabetic users. The results/information available can be the result of evaluation and even referrals for doctors to know in order to effectively and efficiently prevent/control diabetes. The following is the quality of the information contained in the diabetes mobile application: - Informative Informative is the ease and completeness of access to information that allows users to fulfill their information needs. This informative research covers the fulfillment of user information needs on a diabetes mobile application; - Comprehensiveness A mobile device application must have an orientation as the purpose of developing the application. The diabetes mobile application is able to answer the needs of users, both diabetic and non-diabetic. This is indicated by the features/services provided, which are able to adapt to the divinity of the user.

). An application user will feel comfortable using the application if it has a good level of trust. The development of the type 2 diabetes mellitus mobile application includes the following trust components.

4.3. Unified Modeling Language and Design Testing

Software testing is critical because everyone makes mistakes when developing software. Each software program’s errors will be distinct. Therefore, it is necessary to conduct software testing to verify and validate that the program or application created meets the requirement. If it is not the same as what is needed, it is necessary to evaluate it so that improvements can be made to the software.

• Use Case Diagram

The Use Case diagram in the development of diabetes mobile applications will describe the interaction relationship between the system (diabetes mobile application) and the actors involved in the system. The diagram will fully and sequentially describe existing business processes and activities and describe the contents of the diabetes mobile application, where in this diabetes mobile application, the Use Case Diagram is formed from (Figure 3):

• Actor (two actors): The actor (User) is the user of the diabetes mobile application, and the other actor (Software Engineer) is the application developer;
• Use case (10 use cases): Create an Account, Register to IoT Pack, Notification, Alert Setting, Monitoring Medication, Monitoring Food Intake, Monitoring Exercise, Monitoring Sleep, View and Manage, and Access System;
• Association (18 associations): Association between the actor (User) and Use Case, Create an Account, Register to IoT Pack, Notification, Alert Setting, Monitoring Medication, Monitoring Food Intake, Monitoring Exercise, and Monitoring Sleep. Association between the actor (Software Engineer) to Use Case Access System, View and Manage, Create Account, Register to IoT Pack, Notification, Alert Setting, Monitoring Medication, Monitoring Food Intake, Monitoring Exercise, and Monitoring Sleep.

Actors, use cases, and associations are interconnected and interact in one system (the mobile diabetes application), where each actor has different access rights in the system, and each use case will be associated with different actors or use cases according to the system that has been designed.

• Activity Diagram

Activity diagrams in the system (diabetes mobile application) are sequentially described in an algorithm, where each process is carried out in parallel from the start to the finish point. In the design of the diabetes mobile application activity diagram, it consists of (Figure 4):

• Start Point/Initial State;
• Activity (13 activities): Authentication, Forgot Password/Register, Access and Evaluate Data, Report, Data Analytics, Register IoT Pack, Transfer Data, Receive Notification, Medication, Food Intake, Exercise, Sleep, and Recommendation;
• Decision (two decisions): Decision After Activity (Authentication) and Decision after Activity (Recommendation);
• Synchronization (two forks, one join): Fork after Decision of Activity (Authentication), Fork After Activity (Data Analytics), and 1 Join After Activities (Medication, Food Intake, Exercise and Sleep);
• End state.

• Data Flow Diagram

The data flow diagram in the diabetes mobile application will describe the flow of data from the existing system in the application, where we can see the input and output of each process in the form of a design model consisting of (Figure 5):

• Functions (two Functions): Username/Password and User ID Validation;
• Input: User;
• Output: Application;
• File/Database: Database of User;
• Flow (seven Flows): Input (User) to Function (Username/Password), Function (Username/Password) to File/Database (Database of User), File/Database (Database of User) to Function (Username/Password), Function (Username/Password) to Output (Application), Output (Application) to Function (User ID Validation), Function (User ID Validation) to Output (Application), and Function (User ID Validation) to Input (User).

We analyze several factors that will be used as reference material for testing after the system (the diabetes mobile application) is implemented or used by the user after designing use case diagrams, activity diagrams, and data flow diagrams. We formulate five main trust factors (

Table 10. Trust Factors.

No	Trust Factors
	Factors	Variable
1	Functionality	Quality of Information
		Core of Function
		Personalization
2	Ease of Use	User Interface Design
		Efficiency
3	Usefulness	Usefulness
4	Security and Privacy	Security and Privacy
		Authentication
5	Cost	Cost

) in our proposed test, starting from the Functionality (Quality of Information, Core of Function, and Personalization), Ease of Use (User Interface Design and Efficiency), Usefulness, Security (Security and Privacy, Authentication) and Privacy and Costs. Figure 6 and Figure 7 and

Table 11. Demographic Results for Trust Evaluation of the Mobile Application Version 1.

Demographics	Full (N = 40)		Mobile App (Version 1) (N = 40)
	Frequency	%	High Trust Group		Low Trust Group
			Frequency	%	Frequency	%
Sex
Female	24	60	11	45.83	13	54.16
Male	16	40	5	31.25	11	68.75
Education
High School	5	12.5	4	80	1	20
Undergraduate School	30	75	5	16.66	25	83.33
Graduate School	5	12.5	2	40	3	60

and

Table 12. Demographic Results for Trust Evaluation of the Mobile Application Version 2.

Demographics	Full (N = 40)		Mobile App (Version 2) (N = 40)
	Frequency	%	High Trust Group		Low Trust Group
			Frequency	%	Frequency	%
Sex
Female	24	60	22	91.66	2	8.33
Male	16	40	13	81.25	3	23.07
Education
High School	5	12.5	5	100%	0	0
Undergraduate School	30	75	28	93.33	3	7.14
Graduate School	5	12.5	4	80	1	30

show the results.

Researchers conducted an evaluation stage on the development of a diabetes mobile application for 40 participants who were users of mobile-based diabetes applications (diabetic patients). The user’s trust evaluation for mobile applications (Figure 7) adapts to five main trust factors (Table 10): functionality, ease of use, usefulness, security and privacy, and cost factors. The average value of each factor: functionality is 4.57; ease of use is 4.67; usefulness is 4.75; security and privacy are 5.0; cost is 4.70. The values as based on the results of the evaluation using a Likert scale of strongly agree, agree, neutral, disagree, and strongly disagree with an assessment weight of 5, 4, 3, 2, and 1, respectively. Based on the results of this evaluation, two indicators, namely the functionality and ease of use factors, have an evaluation with an input value of 3 (neutral).

Table 13. Mobile Application’s Feature Comparison.

No	Mobile Application
	Feature	Version 1	Version 2
1	General
1.1	Speed	x	✓
1.2	Navigation	✓	✓
1.3	Optimization	✓	✓
1.4	Internet Requirement	x	✓
1.4	File Storage and Sharing	x	✓
2	Services
2.1	IoT Pack
	a. Wearable Band	✓	✓
	b. Treadmill	✓	✓
	c. Gym Cycle	✓	✓
2.2	Medication
	a. Morning	✓	✓
	b. Afternoon	✓	✓
	c. Night	✓	✓
2.3	Food Intake
	a. Intake Recommendation (Breakfast, Lunch, and Dinner)	✓	✓
	b. Adjustmen Option	x	✓
2.4	Exercise
	a. Monitoring Through IoT Pack	✓	✓
	b. Monitoring Through Steps Counter in the App	x	✓
2.5	Sleep
	a. Evaluation/Result	✓	✓
	b. Suggestion	x	✓

describes the representations of the comparison between versions 1 and 2.

5. Summary and Conclusions

The development of the type 2 diabetes mellitus mobile application at the development stage involves an operational feature that allows an application to run according to specified requirements. Testing is a very important stage and must be performed in software development. Tests must be carried out completely and thoroughly in order to cover all possibilities that may occur during the operation. Testing can demonstrate that the application meets the requirements and is error-free. If an error is found, it can be immediately corrected so that it can guarantee the quality of the software being developed. The testing design will boost application development success rates, allowing applications to be useful and optimally utilized by both patients and doctors involved in the treatment of type 2 diabetes mellitus (T2DM). Based on the trust evaluation results for mobile applications, we still need to update several indicators, specifically in terms of functionality and ease of use. Of course, this is a reference for us in developing this mobile-based diabetes application because the development of this application is still in the process of involving 40 participants who are diabetic patients. This study is also intended to serve as a reference for researchers who are currently conducting or will be conducting research in the field of developing type 2 diabetes mobile applications.

6. Future Work

Future work will aim to integrate our project mobile diabetes application with SmartPlate. In the future, through mobile diabetes applications and SmartPlate, patients and users with diabetes/non-diabetes can easily control their health through diet, activity, medication, and even control using a glucometer.