I'm in the same boat. And I came across 2FAS (Android) (Website).
It doesn't have a dedicated desktop app, but it does have a browser extension, which I think is the best we're going to get.
I spent a fair amount of time looking around for an alternative when Authy announced they're killing their desktop app. 2FAS is the best I found.
If anyone else has a good suggestion, I'm all ears.
My requirements:
- Android App
- Desktop App (Linux only)
- Synchronization between the two
- (not a hard requirement) FOSS, or at least just Open Source
I'd be willing to pay for a decent solution.
I didn't realize it at the time, but Authy locks you in with no way to export your tokens. There are unofficial scripts on GitHub, but I haven't tried them yet.
Edit: specified Linux desktop. I don't use Windows.