This is for Android.

Goto Setting>>security>>Smart Lock

Method 1. Facial recognition.

Android offers facial recognition inbuilt in its OS. You can use your front camera to recognise your face and unlock your phone. Thus, eliminating the need to enter a password.

Method 2. Trusted Place.

Android users can use this Tip if they unlock their phone a lot at a certain place like home, etc. Android will automatically unlock itself and not ask for lockscreen password at this location. You can set as many locations as you want.

Method 3. On Body Detection.

This is rather one of the best smark lock in Android. The phone will automatically detect when it is set down and not being held by the user, and thus lock itself. It won’t ask for a password when it is in your hand, pocket or bag.