Also, check out andOTP on F-Droid: https://f-droid.org/en/packages/org.shadowice.flocke.andotp/

Open source and supports backups.

andOTP is amazing, I thoroughly recommend it.

Had no idea about this. I liked Google's Auth since it was simple but it missed the crucial backup feature. Authy is nice but you're putting trust in a 3rd party that doesn't have a channel for donations, though it seems they're making money through SMS (Twilio).

andOTP is just what I was looking for since it's FOSS and had backup! This would have been a lifesaver when I lost my phone but glad to have run into it now.

TOTP is old and busted, U2F is the new hotness.

https://en.m.wikipedia.org/wiki/Universal_2nd_Factor

> The device key is secured against duplication by a degree of social trust in the commercial manufacturer

TOTP sounds much better. Also doesn't requires "trusted magic hardware"

U2F prevents some vulnerabilities that TOTP alone can't. It's possible to replicate it in software instead of a hardware token, but so far nobody has. So if you're adopting 2FA, suggestion is to use U2F if you can.

Thanks for the tip, I only knew about authy before