Set up automatic phone unlock when you’re at home.

             Smart unlock” is a new feature in Android 5.0 Lollipop. It removes your phone’s PIN or passcode in certain locations you trust, like home or work. Go to Settings > Security > Smart Lock > Trusted places and add to trusted places.
If your device is running Android 4.4 KitKat, there is a smart workaround for this. Enable installation from third-party apps by going to Settings > Security > selecting Unknown sources. Then follow these instructions.