## 4 Implementation, Results, and Discussions
### Application Navigation and Features
#### 4.1.3 Main Menu
In Build 1 and 2, a single \"+\" marker representing a particular muscle selection touch input was interactive (Figure 4a); once tapped, the particular interactive muscle name would appear to allow the user access to an information panel overlay with more information on the muscle origin, insertion, innervation, action, and gifts, as well as voice-over audio with the same content (Figure 4a, e.g., Brachioradialis). Eventually, the \"+ then pin\" marker was removed, and replaced by Build 8 with a single tap touch input to highlight and interact with the model in an easier manner (Figure 5, e.g., Biceps brachii). However, the information and audio files were only functional by Build 9, and by the 10 th build its visual design was improved with the addition of gifts of the muscle function (Figures 4b and 5; e.g., Biceps brachii). (ii) AR mode immersive functionality  
The AR mode is designed similarly to the 3D mode, with the exception of required access to the mobile device camera to detect a flat surface to \"spawn life-size\" models in the real-world environment. Originally, the AR feature was developed using AR Foundation in conjunction with the ARCore SDK, where the user would encounter the AR mode with the use of their mobile device camera. The camera would detect and utilize a flat surface to produce an interactable \"purple ring surface indicator\" required to tap on the screen and \"spawn life-size\" models in the real-world environment (Figure 7a). However, by Build 7 the application made use of Vuforia marker-less ground plane detection as this made it easier to \"spawn life-size\" models and avoid the instability of the models displayed when using AR Foundation (Figure 7b). The platform change was also easier to operate/navigate in terms of scripting. To add a layer of immersiveness and increase user interest, another difference is the placement of the muscle labels and muscle information panels that were relocated in Build 7 to display next to the model (World UI) as opposed to on the screen overlay (Figure 7b). The final progression of the AR mode can be seen in Figure 8.  
3. Glossary  
The glossary contains tables with more detailed information on the muscles, bones, and nerves. Initially, two of three system UI buttons were inactive, and only the musculoskeletal system was active with sample images being used to represent the musculoskeletal system table of information (Figure 9a). However, by Build 5 all of the UIs were active with relevant sample images for each system as well as the addition of \"next\" and \"previous\" UI buttons. Finally, in Builds 6 to 8, the sample images were replaced with functional interactive (scrollable) Unity tables, a simple table UI, which is an asset from the Unity asset store, so as to display the tables optimally and improve user experience (Figure 9b). The progression of this feature, including the final UI design and placement, can be seen in Figure 9.  
The scoring system underwent various programming and design changes from the original layout design planned (Figure 10a). In Build 3, the incorrect scoring system was removed. It is important to note that a functional scoring system (score and high score) was only achieved in Build 7. However, by Build 9 the high score was removed due to persistent bugs and coding errors. In Build 10, the final changes to the design of the scoring system was made (Figure 10c). Originally, all of the diagrams used in the quiz feature were sourced from Kenhub, however, due to copyright issues these images were replaced with original images (Figure 10c). The progression of this feature, including the colour palette and UI design and placement, is shown in Figure 10.  
The main menu also allows access to an accessory feature, Help, which provides the user with a detailed explanation of how to navigate the application (Figure 11). Initially this feature was developed to provide explanations of the navigation touch inputs (hand gestures) and UI icons (Figure 11a).