I didn't know when I installed the GitHub recommended authenticator on my Android that it was going to be nagware. Upgrade to Pro! messages on my phone at intervals.
@rdviii I can tell you that I use a different one for GitHub, suggesting that you can use any authentication app that implements standard TOTP (which is defined by RFC 6238). A few apps I've seen recommended are Duo, Authy, and Aegis. I've used Authy and it does the job with no annoyances I've encountered (just make sure you disable adding additional devices to your account if you don't immediately need to do so) or you could go with something like Aegis if you prefer open source.
@internic thanks. Come to think of it I might have another already installed. Will consider switching.
@internic a thing literally called Authenticator.