Malicious Video Circulating That Will Freeze Any iOS Device
Only a hard reset can solve the problem.
When using your iPhone, who will usually get messages from friends with a video link. But be careful. Apparently there is a malicious one circulating that will slow your any iOS device to a crawl before freezing it altogether.
The video is only three seconds long, but when played in any iOS (from 5 to the current 10.2 beta 3), the device will work normally for a few seconds, but gradually slow to a crawl and eventually become unresponsive. The good news is that a hard reset of the phone or device will clear the problem immediately.
It isn't clear what about the video causes the problems, but if you get it, at least you know it won't brick the device.
The video below from EverythingApplePro (via 9to5Mac) shows the issue and how to fix it. The video he is discussing is listed in the YouTube info. If you do feel like pranking a friend, be nice and tell them how to fix it.