How to turn your Home button into a Camera app shortcut like on the Galaxy S6 & edge

The Samsung Galaxy S6 & edge have this nifty feature of quickly launching the Camera app by just double-tapping on the physical Home button. But the cool party trick is that you can replicate part of the same functionality on any ol' Android smartphone (well, unless you're still running Gingerbread). The app Home2 Shortcut lets you assign whatever shortcut you please to any of your device's capacitive or software navigation buttons, then specifiy a gesture (double tap or something different), set a duration, and have your way! No root needed!