Perceived ease of use on visual learning application for mathematics using holography display for the topic on shape and space [version 1; peer review: awaiting peer review]

Background: A person's life is built on a solid foundation of mathematics. Common causes of learning difficulties in mathematics include abstract ideas, a lack of imagination, and a lack of comprehension of the concepts being studied. Because 3D shapes are abstract concepts, the aim of this study is to better understand how to recognize them in primary school students. Methods: The development of the Mathematics E-Learning Visual application MEL-VIS(MEL-VIS) application involves the design of the Visual Learning Application Iteration-Evolution Development Model, MEL-VIS (PIEMEL-VIS), the MEL-VIS ID Model, and the MEL-VIS Application Module. The development methodology and ID model are built based on the application of various components such as learning theory, a visualization approach, a play-while-learning approach based on scaffolding techniques, as well as interaction and interface based on various touch technologies using tablet computers. The study's contributions are: (i) an iterative-evolutionary development model of the Visual Learning Application, MEL-VIS (PIEMEL-VIS); (ii) a MEL-VIS ID model; (iii) a MEL-VIS application prototype; and (iv) a usability testing instrument for the ease of use of the MEL-VIS application.


Introduction
Shape and space in mathematics are widely used in engineering, architecture, science, and technology. The most significant application of form and space can be found in building design and layout. Because of this clear demand, the theme of space and form has been adopted in the Malaysian national school curriculum from pre-school to higher education, particularly in the fields of design and architecture. 1 Learning about space and shape entails not only learning about the meaning or notions of geometric concepts, but also learning how to analyse two-dimensional (2D) and three-dimensional (3D) shape characteristics in geometric shapes. 2 Furthermore, students can debate geometric relationships to identify position and space in geometric relationships, then change and use symmetry, visualisation, spatial thinking, and geometric models to solve problems. 3 Geometry is defined by Bassarear and Moss (2015) as "the study of shapes, relationships, and properties." According to Aulia,4 geometry is the study of space and form, and better reasoning skills are required to understand these concepts well.
Among the difficulties encountered when learning and teaching the topic of shape and space are difficulty identifying and confusing the names of 2D and 3D shapes, difficulty referring to the figure's location, difficulty understanding the figure's characteristics, and difficulty imagining the layout of the 3D shape. [5][6][7] The development of the visual-electronic applications in this study was based on a multi-touch tablet, considering several factors that are suitable for students who prefer visual and auditory learning styles, such as the suitability of the navigation button position, the position of the menu and module interface, the level of interactivity, user-friendliness, assistance, and multimedia-fusion elements such as text, colour, and animation. Built electronic-visual, or E-visuals, applications use strategic teaching and learning processes based on the constructivist approach, the 5E learning approach, and the mastery learning method; they use the concept of scaffolding in the process of guiding students, the method of learning while playing, and active learning. All of this is intended to make primary school students' learning more effective and enjoyable. All the implications of the teaching and learning strategies, approaches, methods, and concepts used in the built visual-electronic or E-visual applications have also been discussed, considering previous studies and reforms implemented in the studies.

MEL-VIS visual-electronic application design
The development of an E-visual application for teaching and learning based on holographic displays. The development of the Mathematics E-learning visual application (MEL-VIS), is a prototype application for learning mathematics for primary school students. The prototype of the E-visual application can create a more effective learning environment where the instructor acts as a guide to the students. Instructors introduce how to use the MEL-VIS application to students, and students can conduct their learning independently based on the concept of self-pace and self-learning. The MEL-VIS Prototype application development process involves several phases based on an agile model called the MEL-VIS Application Iteration-Evolution Development Model (PIEMEL-VIS) which is systematic taking into account the SDLC-Waterfall Model, the Prototype Process Model 8 and Content Prototype Iteration Model. 9 Figure 1 shows the iterativeevolution development model of mathematical E-visual application (PIEMEL-VIS).
The design of the E-visual MEL-VIS application was inspired by the skeuominimalist design. Skeuominimalismis a term that combines skeuomorphism and minimalism. 10 A skeuominimalist design reduces app usage from human error and allows users to have more interactive experiences with apps. [11][12][13] As shown in Figure 2, the MEL-VIS visual-electronic learning application is comprised of three (3) primary modules: the 'Let's Read Module', the 'Let's Recognize Shapes Module', and the 'Let's Learn Shapes Module'. Students must finish the 'Let's Practice' submodule and the 'Let's Play' submodule for each module indicated. Overall, the MEL-VIS modules' learning method is founded on the 5E Approach, learning while playing, and digital exploration via serious games. According to few researchers, [14][15][16] learning via gaming increases learning interest.

Introduction of visual-electronic application: MEL-VIS
To attract primary school students to the E-visual application, MEL-VIS, an introductory montage of the MEL-VIS application is broadcast when the application starts. The montage consists of form elements and the introduction of cartoon characters that appear in the application. The MEL-VIS montage was developed using Adobe Flash CS6 authoring software and loaded with 2D and 3D vector animation elements. The purpose of introducing the application through montage is to allow primary school students to better remember this application and stimulate their instinct for curiosity by revealing various basic forms of visual animation at the beginning of the E-visual application MEL-VIS for learning mathematics. Figure 3 shows the introductory montage interface of the E-visual application, MEL-VIS.  Various basic shapes and colourful numbers can be seen to create excitement for primary school students before they start learning. The 3D shape animation in the montage is relevant to the topic of shape and space. Through the montage display, students can recall what they learned in their long-term memory. Figure 4 shows the interface of the learning E-visual application, which is called E-visual application for primary school mathematics subjects, MEL-VIS. Animations of cartoon characters and objects are created to attract the attention of primary school students before starting mathematics subjects using the application. The application also introduces characters that appear to attract students' attention. The screen is accompanied by music, animation, text, and colour combinations to attract students' interest, create curiosity, and increase their willingness to continue learning. This is in line with pattern recognition-cognitive theory: a template based on pattern recognition theory introduced by Reed 17 and a cognitive approach emphasising the use of curiosity and individual achievement as motivation in the learning process. 18 Menu of the visual-electronic application: MEL-VIS The main menu interface has three (3) main modules and two (2) sub-modules: the Let's Read module, the Let's Recognize Shapes module, the Let's Learn Shapes module, the Let's Practice sub-module, and the Let's Play submodule, as can be seen in Figure 5. In the main menu, soft and entertaining background music is played, aiming to attract primary school students to explore each module and sub-module available in the application. Graphic buttons with labels are used as navigation buttons for the E-visual MEL-VIS application prototype interface. According to few researchers, 19-21 the use of both graphic and text navigation icons makes it easier for novice users to explore new applications as compared to using only graphic navigation icons or text navigation only. Using interactive icons that function as elements, students can build knowledge through independent exploration (constructivist theory) and active learning (active learning).
Let's Read module of visual-electronic application: MEL-VIS The Let's Read module of the prototype E-visual application, MEL-VIS, aims to teach primary school students to recognise 3D shapes, which is one of the important syllabuses in primary school mathematics subjects. Through the Let's Read Module, students learn 3D shapes such as cones, spheres, cuboids, cubes, cylinders, and pyramids through reading poems and watching interesting animations. All the 3D shapes introduced in the poem are closely related to everyday life.  Students can organise their thoughts about learning outcomes and make connections between the knowledge they have learned. This is in line with the 5E learning strategy, the engagement phase.
Some researchers think that the use of rhymes is an important technique to help students remember learning because the human brain easily connects with sounds for long-term memory. [22][23][24][25] Animated interactive objects that serve as aids and guides for students to remember (Cognitivism Theory). In teaching, poems or rhymes can help change the learning environment to be more interesting. Figure 6 is one of the Let's Read Module screens.
Let's Recognize Shapes in visual-electronic applications module: MEL-VIS The Let's Recognize Shapes module is a learning module for recognising 3D shapes. Figure 7 is the start screen of the Let's Recognize Shapes module of the prototype E-visual application, MEL-VIS. The concept of scaffolding is applied in this section; guidance in the form of animation and audio is displayed for students as a guide to exploring this module. Figure 8 shows that the students can touch the 3D shape to hear the pronunciation of the shape, and the animation will also   be displayed. In addition, the selected 3D shape changes the display with brighter and more attractive colours. This may pique the interest of elementary school students in observing the learned forms. The 5E method (engagement phase and exploration phase) has been applied in the design of the Let's Recognize Shapes Module.
The Let's Recognize Shapes module is built using the flash card concept. The use of flash cards is often recommended as an effective learning method for students. [26][27][28] The use of this concept in the Let's Recognize Shapes Module can effectively help students recognise 3D shapes in long-term memory. Students can relate the 3D shapes they have learned to real 3D objects they can see around them using flash cards, as shown in Figure 9, which helps them understand what they are learning. The movement of the human eye moves according to the location of the object on the screen. On the Let's Recognize Shapes Module screen, all animated objects are placed symmetrically. Through that method, primary school students have the understanding to distinguish 3D shapes with different characteristics.

Module Let's Learn Visual-Electronic Application Shapes: MEL-VIS
The Figure 10 and Figure 11 show the initial interfaces of the Let's Learn Shapes Module. At the beginning of this module, there is an exploration guidance animation (Scaffolding Concepts). In addition, the concept of scaffolding is also applied to the help button ( Figure 12) to guide students on how to use pyramid holography. This module is a mathematics learning module that explores the topic of 3D shapes in more depth with a holographic display that can be seen in Figure 13.
The students can choose the shape they want to learn for a more thorough and in-depth description of the shape. For example, students choose a pyramid shape. Aa description of the characteristics (vertices, surfaces, and sides) of the pyramid shape in animation and audio will be displayed. Animated learning functions as an element that activates sensory memory, namely short-term memory and long-term memory (Cognitivism Theory), which aims to interest and encourage students to ask questions (Constructivism Theory). The 5E learning strategy (engagement (engagement), exploration (exploration), explanation (explanation) and further explanation (elaboration) is applied in the design of the Let's Learn Shapes module. The students get involved, explore 3D shapes and in addition, can add knowledge through explanation and further explanation of 3D shapes through holographic displays. This can help students with the processes of shortterm memory and long-term memory (concept of constructivism).

Sub-Module Let's Practice of visual-electronic application: MEL-VIS
There are three categories of questions out of a total of twelve questions in the Let's Practice sub-module. In the first category (i), basic questions differentiate 3D shapes; in the second category (ii), questions consist of the characteristics of 3D shapes; and the third category (iii) is related to 3D shapes in daily life. The questions in the E-visual application prototype (MEL-VIS) are randomly generated every time. The questions provided in the module involved are according to the syllabus for the primary school mathematics subject and have been confirmed by three (3) experienced mathematics teachers. Also, the 5E learning strategy (Evaluation Phase) is applied in this sub-module. Figure 14 to Figure 16 are examples of questions in the Let's Practice sub-module of the prototype E-visual application: MEL-VIS.

Sub-Module Let's Play of visual-electronic application: MEL-VIS
In the Let's Play sub-module, primary school student complete tasks in stages through storytelling exploration. Based on this sub-module, students need to master each step to proceed to the next step. This is in line with active learning and mastery, or basic learning. The concept of serious games is also applied in the Let's Play sub-module, where learning objectives are achieved after completing the sub-module tasks. Through the Let's Play sub-module, two-dimensional (2D) and three-dimensional (3D) animation forms are used to narrate throughout the exploration of Iqa. Iqa is the main character in this story. Students are asked to help Iqa until she reaches home. The assignment given to students is related to the topic of basic 3D shapes in mathematics subjects. Figure 17 to Figure 20 are examples of the display screen of the Let's Play sub-module prototype of the E-visual application, MEL-VIS.   This Let's Play sub-module is also used to test the understanding and memory of primary school students about the 3D shapes that have been learned. The action that primary school students need to take for this sub-module is to drag the 3D shape label and place it on the correct 3D shape. The use of 3D shape labels instead of 3D shape images in the task is because six experienced teachers think matching labels with images is more effective in learning. This can help students achieve "higher mental function." In addition, encouraging students to seek answers and think critically (Constructivism Theory).
To increase students' level of understanding in learning sessions, scaffolding plays an important role. Scaffolding enables primary school students to master their learning level step by step and also provides assistance through animation. Through this sub-module, step-by-step help is presented through animation to give students ideas on how to complete the given task. Scaffolding is adapted into some of the Let's Play sub-module activities, as shown in Figure 21. Table 1: Scaffolding Strategies in the Let's Play Story Plot shows the scaffolding strategies found in the Let's Play submodule's story plot, as well as where the concepts of learning while playing and serious games have been applied in the application. This strategy can arouse curiosity, attract the will to be involved, cultivate the will to think, and apply

Arousing curiosity
The beginning of the story has interesting elements, one of which is the arrival of the main character in a spaceship flying through the air.
Attracts the will to engage The next storyline attracts students to get involved as the main character asks for help in exploring the way back home.
knowledge. The Let's Play sub-module is built based on the MEL-VIS Human and Computer Interaction Model (HCI: MEL-VIS Model), as can be seen in Figure 22.

Methods
Summative testing through usability testing was carried out at a primary school in Putrajaya, involving a total of 80 students aged nine years during the COVID-19 pandemic lockdown. During this period physical distancing was enforced. Therefore, an oral information-giving and consent-seeking process had been conducted by school authorities. During the testing, a briefing was given to all students involved in usability testing. The post-test is administered to all students who participated in the pre-test. Students are given a ten-minute trial session using the E-visual, MEL-VIS application. After that, they were asked to complete the list of assignments given. Student performance in completing each task is recorded for analytical purposes. After finishing using the E-visual application, MEL-VIS, students were asked to complete a questionnaire about the application. Questionnaire: A set of questionnaires was constructed and administered to students after they used the prototype of the MEL-VIS application with the help of the teacher. The questionnaire has four questions and aims to test the constructs of ease of use and ease of learning. Task list: The task list is intended to put the construct of usability to the test. All the tasks that the students must do are stated in the list. Students are required to complete a list of assignments totalling 20 steps using MEL-VIS. A total of eight steps concentrates on the main menu, six on the use of the holographic display, three on the training sub-module, and three on the Let's Play module. Testing for usability constructs is based on observation. Observations are recorded through performance indicators. When the students used the E-visual MEL-VIS application prototype for the first time, the researcher himself observed the procedures. All these tasks are the main interactions in the E-visual MEL-VIS application. The results of observation are recorded through student performance indicators, as shown in Table 2.  In the exploration with the main character, the storyline is composed with a logical sequence that encourages the will to think among the students. 2D and 3D illustrations and animations encourage students to think and focus on the situation raised during exploration.

Apply knowledge
The students can apply the knowledge that has been gained from the application to their daily lives. For example, understanding 3D shapes that have been learned and relating them to everyday life objects.

Results and discussion
The following research findings are based on the research question: Is a visual electronic application, developed using a holographic display based on multi-touch technology, easy to use by primary school students for mathematics lessons?
The ease-of-use construct process is based on the ease-of-use construct data analysis model, which can be seen in Figure 23. Table 3 shows the mean average success of students in implementing each type of instruction given according to the Steps. The study found that 89.00% of students successfully implemented the researcher's instructions in the main menu, 91.33% of the students successfully implemented the researcher's instructions in displaying the 3D holographic display, and 95.67% of the students successfully completed the instructions given by the researcher in the Let's Practice sub-module. The highest success by students is in implementing the instructions in the Let's Play sub-module, which is 96.67%. Table 4 shows the average mean student performance for each task step given. Based on Table 3, the increase in the mean average success rate of students successfully executing the given instructions increases from the main menu to the Let's Play sub-module. This shows that the students can adapt easily when using the E-visual MEL-VIS application.  Based on each test conducted, primary school students have given positive feedback to the prototype of the E-Visual MEL-VIS application. Thus, it can be concluded that the prototype of the E-visual MEL-VIS application is effective, easy to learn, and easy to use for student use in primary school mathematics subjects.

Conclusions
This study has produced research findings involving the development of an E-visual application prototype using a holographic display based on multi-touch technology and the evaluation of the MEL-VIS E-Visual application prototype for primary school students. An agile or agile methodology specially designed for the development of prototype E-visual MEL-VIS applications was built, which is the MEL-VIS Application Iteration-Evolution Development Model (PIEMEL-VIS), which involves five phases, namely: analysis, design, development, implications, and evaluation. The model is both a theoretical and practical contribution to the application development process for primary school mathematics learning. Based on this study, the application was designed and developed using the MEL-VIS E-Visual Application Prototype ID model that takes the needs of primary school students into account. The ID model is used in the application design and development process based on the content of the user requirement specification (URS) and system requirement specification (SRS). This study also produced a scaffolding model that was used as guidance for primary school students to use the E-visual application prototype more effectively.
This study on usability testing received a positive response. This shows that the development methodology and the builtin ID model successfully improve the usability of the E-Visual MEL-VIS application prototype. However, there is still room to refine the development of the application from a technical point of view and further diversify the content of the application. Overall, the research findings show that the prototype E-visual MEL-VIS application is effective in improving students' understanding and achievement and is easy-to-use.  This project contains the following underlying data: • Data file 1-4 (Task List Data in.dat and.sav format).
• Data file 5 (MEL-VIS E-visual application task list: usability test in pdf format).
• Data file 6 (Letter request permission to conduct testing in.pdf format).
• Data file 7-8 (Confirmation of study approval in.pdf format).
Data are available under the terms of the Creative Commons Zero "No rights reserved" data waiver (CC0 1.0 Public domain dedication).

Ethical approval
Ethical approval Reference Number from The National University of Malaysia (approved by Institute of IR 4.0 (IIR4.0)): UKM.IIR.800/1/3. Informed consent was gained prior to data collection.