How do I quit a running app / kill an app in iOS 7?
The app switcher in iOS 7 has been redesigned by Apple. One of the new things that iOS 7 users will see is that the multitasking dock no longer shows simple app icons. There's a preview of the entire app screen above the icons. So how can you stop an app from running, or remove its preview and icon from the app switcher?
To quit an app in iOS 7 follow these instructions:
1. Double press the home button to bring up the app switcher.
2. Swipe left or right until you see the app to quit.
3. Touch and hold the app preview and swipe it up off the screen.