I don't know if it's just because I am a custom ROM developer and wipe my phones very often, but I personally consider all data on my smart phones ephemeral and need to be backed up somewhere else. This means that 2FA apps like Google Authenticator which basically bind all of my 2FA keys to one single device are no-go for me.
Maybe I should jerry rig together some simple and dumb device that does and only does TOTP.
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