Do not support Xiaomi (android 4.4). Wave unlock is app unlock the screen by waving hand over proximity sensor. [NOTE]. If you can unlock, please open settings and enable "Unlock" function to retry. [Feature]. Wave hands over proximity sensor to lock and unlock screen. You can use smart cover to automatic turn on/off screen. Allow set sensitivity for proximity sensor. Helps you to prevent your Power button or home button for broken. Applications work fine, no errors on the device. If app not working you please send request: dovanhoang. firstname.lastname@example.orgIf you like the app, don't forget rate five stars. or review. They are appreciated for me. Thank you so much.