If your device supports fingerprint authentication using the standard Google API (Nexus Imprint) you can enable this to log into your Lockr.
Some devices have fingerprint readers that use their own custom system (e.g Samsung). You cannot use fingerprint login with these devices. Nexus Imprint is the Android standard and the only supported system.

To enable this function, your device must be secured by a Password or Pin and your fingerprints should be registered in the device settings.

Log in as normal, and open the navigation drawer. Under the "Change Password" option will be an "Enable Fingerprint" option. This option will NOT appear if your device is not compatible.

Press the option and you will be asked to confirm by touching your fingerprint reader sensor.  Once done, you can log into the Lockr with your fingerprint.

A fingerprint icon will appear on the login screen to indicate that fingerprint access is enabled. Even with fingerprint access enabled, you can still log into your Lockr using your password or pin as normal.  Fingerprint access is an additional option rather than a replacement option.

Fingerprint login is specific to each device. If you share your Lockr with other devices, the option will need to be enabled on each device.

Fingerprint access will need to be enabled again if you change your password or if you register additional fingerprints in your Nexus Imprint settings. You can also disable fingerprint access by performing these operations.

Hint: If you want to disable fingerprint access but do not want to change your password, simply go through the password change procedure but use the same password.

NEVER rely solely on fingerprint login. You MUST ALWAYS remember your password.
There are various events that can cause the fingerprint to need to be re-enabled and you cannot do this if you can not log in.