That heart rate sensor on the back of your Galaxy S8 can actually be useful for something

As far as gimmicks go, Samsung's insistence on shoving a heartbeat sensor on the back of its flagships, including the latest Galaxy S8, is a pretty unobtrusive one – in fact, chances are most users aren't even aware of the feature's existence. But, as it turns out, being an unnecessary gimmick doesn't mean it can't have actually useful built-in functionality as well.

If you're anything like me, selfies can be uncomfortable to take sometimes, and particularly so with a larger device. Certain poses and angles can make the on-screen button hard to ...