OTP Auth is described as 'The app for calculating one-time-passwords on iPhone and iPad. OTP Auth can be used with any service that uses one time passwords. This includes services like Dropbox and GMail with two-step-verfification enabled. OTP Auth is QR code enabled' and is a Authenticator in the security & privacy category. There are more than 50 alternatives to OTP Auth for a variety of platforms, including iPhone, Android, iPad, Android Tablet and Mac apps. The best OTP Auth alternative is Aegis Authenticator, which is both free and Open Source. Other great apps like OTP Auth are Proton Authenticator, Ente Auth, Bitwarden Authenticator and 2FA Authenticator (2FAS).