How do you do a hard reboot w/ touch ID on iphone 7. - Also, this was a great trick - and don't know how this works either: To shut down all your open apps, you might know that you can double-click the iPhone's home button and swipe up on each one in the app switcher. For a shortcut (and a way to clear your phone's memory), try this: From your home screen, press and hold the power button until the "slide to power off" screen comes up. Then, let go of the power button and hold down the home button until your home screen pops back up. That's it! If you look at your app switcher, all your open apps are still there, but when you open each one, it will re-launch that app from scratch.