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 August 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 extremely loud scream 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.