If you own an iPhone 5S and you use Touch ID to unlock it, you may have noticed that it sometimes displays a “try again” message, indicating that Touch ID did not recognise your finger. 

A beautiful tip shared by Lun Esex on Monday Note offers an elegant solution:

Register that one finger twice with TouchID, as if it were two different fingers. It will then have twice as many datasets to compare against that finger when using it to unlock the device.