Oddbean new post about login | logout Sure, if people can paste that into a browser and things just work that would be better. But I don't think they can do this right now.
A custom app URI only works for native apps. But it’s shockingly easy to implement because you don’t need to get it registered as an officially supported protocol in browsers. https://developer.apple.com/documentation/xcode/defining-a-custom-url-scheme-for-your-app https://developer.android.com/training/app-links/deep-linking