Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens for your online services.
Authy is a simple way to manage two-factor authentication accounts. Authy supports Gmail, Dropbox, LastPass and thousands of other sites.
It implements Time-based One-time Passwords (TOTP) and HMAC-Based One-Time Passwords (HOTP). Simply scan the QR code and login with the generated 6-digit code.
Unmaintained, see https://github.com/andOTP/andOTP and developers announcement on XDA https://forum.xda-developers.com/t/app-4-4-open-source-andotp-open-source-two-factor-authentication-for-android.3636993/post-87021655
andOTP vs FreeOTP opinions
Google Authenticator generates 2-step verification codes on your phone.
Enable 2-step verification to protect your account from hijacking by adding another layer of security. With 2-step verification signing in will require a code generated by the Google Authenticator app in add.
Sign in is easy, convenient, and secure when you use Microsoft Authenticator. Use your phone, not your password, to log into your Microsoft account. You simply have to enter your username, then approve the notification sent to your phone.
Open the app in one tap, sign in with FaceID and copy your one-time password to your Mac in one tap with handoff. Using a one-time password manager has never been easier!
FreeOTP+ is a fork of FreeOTP with an updated user interface and with backup/restore functionality (to external files or via built-in Android backup/restore).
FreeOTP+ (fork of FreeOTP) vs FreeOTP opinions
FreeOTP+ can export your secrets so you can back them up.
Authenticator generates two-factor authentication (2FA) codes in your browser. Use it to add an extra layer of security to your online accounts.
LastPass Authenticator is a two-factor authentication app for your LastPass account and other supported apps. LastPass Authenticator offers simple, secure authentication to your accounts by generating passcodes for login or receiving push notifications for one-tap approval.