This is an alternative to 2FA stock Authenticator (GA), which is based on Time-based One Time Password (TOTP). It integrated well with Samsung's Gear Authenticator Client (GAC) app, which is available in Samsung's App Store since 2015. It has rich backup/restore capabilities, including local phone storage and Google Drive. The latter is very handy for syncing GA accounts on multiple Android devices.
The application can be started locally on Android or remotely from a Gear or Galaxy Watch device. Having a Gear device is not required though. To start it from your Gear device, select "Connect to Phone" menu in GAC application. After the Gear device is connected, many options are available for transferring data between devices. A new account can be created by scanning a QR bar code or by entering a secret manually.
After the QR code scanned or entered manually, you can either send it to Gear by tapping "Send to Gear" button or save it on your phone using "Save" button.
If "Overwrite" checkbox is checked, an existing account will be updated with a new secret or a new one will be created if an account with this name didn't exist.
Gear's GAC application should be in a waiting state to be able to receive any messages from the phone. It means that all communications with the phone are possible only after "Connect to Phone" menu is tapped in your Gear GAC app and while a connection dialog is open.
GA Accounts page shows all accounts created by GAC app and stored on the Android phone.
Tapping an account's name or token on the accounts page will open a zoomed view for a single account. A token in the zoomed view will be updated automatically when an old token is expired. Accounts can be scrolled on this page using left and right arrows.
Press an account editing button on the right to change a shared secret or an account name, or both.
By default accounts are sorted in alphabetical order. Long press an account name and drag it to a new place If you want to change the order.
Accounts can be saved to and restored from an unencrypted or encrypted backup file stored in a local phone's storage or on Google Drive. Encryption is based on a password provided by a user. Encrypted backup will be signed with an HMAC signature to make sure that a backup is not corrupted during a restore operation. Unencrypted and password-less backups are available as well, but not recommended.
This application serves ads, but only for those users who use it without a watch. Ads will not be served any more after at least one successful connection has been made from a watch.
Detailed instructions can be found here: https://credelius.com/credelius/?p=241