So basically what title says.
Im using 2FA with google authenticator for multiple accounts. What if my phone gets stolen? Can I have some kind of backup? Or maybe sync with some self hosted service?
Bonus question: what 2FA should I use instead of google?
I prefer an authentication code, which I can save on a pendrive or, if not, a second email. I never use 2FA with a phone number, precisely because a phone is never secure and is also a privacy hole. It's enough that they know my email, it's not necessary that they also know my phone number.