Thank you! Yeah, obviously the UI is a weak part. I'd like to improve it eventually but as a one-person project I don't want it to have as minimal of an interface as AirDrop. With all the ways transfers can go wrong, I want that information to be in the user's face so they can submit issues and I can help debug easily.

And no, it can't detect anything about the other device until they're on a WiFi network together, and that can't happen until it knows the peer's OS because it has to know whether it or the peer should be hosting the hotspot. Windows has precedence, then Linux, then Android. (The iOS version doesn't need to know the peer's OS because iOS and macOS can't stand up a hotspot programmatically anymore, so it always has to join.)