I can recommend Aegis if you're looking for an open source authenticator app.
It works basically the same (or better) than the Google Authenticator, and you don't need the Google Store to get it.
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AndOTP is another good option.
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AndOTP is not maintained since a while - https://forum.xda-developers.com/t/unmaintained-app-4-4-open-source-andotp-open-source-two-factor-authentication-for-android.3636993/page-6#post-87021655. It is nice indeed, but since it's about security I'd prefer something active to increase the probability to have all the fixes in time.
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Oh wow, good to know.
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bitwarden also doubles as TOTP authenticator
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the best defence is not to use a sim at all
just use wifi and keep your phone in airplane mode
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Any suggestions for where to read more about this?
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