If you’re not ready to get a watch for yourself, you can build an app in the emulator and see what you’re missing.
Another project in the same vein is Slidev. In this project you maintain your slide content in Markdown and can render using custom Vue components. You don’t have to build your own as the included themes are really flexible.
The WebVR API captures information from VR Devices connected to a computer and converts it to useful data that you can use in your own applications.
If you want to reduce the amount of boilerplate you have to write then a project like A-Frame can help. With this project, you can develop from a plain HTML file providing a rich-markup language. It also provides an extended version of three.js (https://threejs.org/) with a more composable and extensible API.
If you want to have greater control over the audio you can use a project like Howler.js. This library is used by companies like Disney and Lego to help build immersive, spatial audio experiences.
Instead, maybe you’d rather create interactive music. A tool like Tone.js might be just what you need. The API for this framework will feel familiar to any audio programmer or digital musician. The demo page for this project is really inspiring with one of my favourites being this pentatonic tone board.