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Get DTS Widget old version APK for Android
Double Tap to Sleep Widget
Widget that allows you to double-tap on your home screen to lock your device.
No root is required.
Perfect solution for users whose device supports double tapping to wake/sleep but want to use custom launcher that doesn't have this feature.
For this to work you must enable this app as Device Administrator
Completely free, not ads or anything
Enjoy
This app uses the Device Administrator permission.