To my dear her
To my dear her (Chinese: 送给亲爱的她) is a screamer application runs on Android devices which spreaded across China in around Aug 2016. It pretends to be a social platform client which has the same name, however it's only 1.5MB while the original one costs around 11MB.
When the user launchs it, a bleeding woman face will appear, volume adjust button on the device will be disabled, and the scream used in Slendytubbies will be played looply. The application will even listen to BOOT_COMPLETE event, which means each time your phone completes its startup progress, this application will be called to run. So reboot won't help. If you don't have a shortcut to kill foreground applicaion, then you will have some time dealing with it.
NOTE: This program could potentially harm your device.