Authenticator is a free Two Factor Authentication (2FA) app that generates Time-based One-time Passwords (TOTP) and PUSH authentications on supporting TOTP websites. This app helps keep your online accounts secure by generating one-time codes that provide an additional layer of protection. Authenticator supports SHA1, SHA256, and SHA512 algorithms and generates new tokens every 30 seconds. With its password protection feature, you can secure your one-time tokens.

The app is easy to use, simply scan a QR code to protect your account. You can also add details manually. At the time of login, copy the token generated by the app and use it for successful login. Authenticator also allows you to view the QR codes of linked accounts and backup and restore created tokens.

Overall, Authenticator is an excellent app for anyone looking to add extra security to their online accounts. Its user-friendly interface and features make it easy to use and a must-have for anyone concerned about online security.