Yes but keep in mind the trail that's loaded is baked into the app. You can't select from a list of trails or anything like that. This is more of a boilerplate

Yes but keep in mind the trail that's loaded is baked into the app. You can't select from a list of trails or anything like that. This is more of a boilerplate for other people to customize. But maybe someone will fork and add that kind of functionality. That being said, it's a web app which means it runs in your browser. Follow the link at the top of the README ("Try it out here"). If you're on Android, open your browser menu and look for a menu item that reads `Install` and tap that to add the icon to your homescreen. Now you can use it as a standalone fullscreen app. If you're on iOS Safari, you can follow the same instructions but install of `Install` it's something like `Add to Home Screen`. Unfortunately Apple doesn't support all the same features because they want to incentivize people using their app store.