FreeOTP is a soft token authenticator that can be used for two-factor authentication. It provides implementations of HOTP and TOTP. Tokens can be added by scanning a QR code or by manually entering in the token configuration. FreeOTP can be used as a replacement for Google Authenticator even when logging into Google services. It is maintained by Red Hat under the Apache 2.0 license. It is available for Android and iOS.
References
FreeOTP Wikipedia(Text) CC BY-SA