iOS 7 How-to: Set up Automatic App Updates
In earlier versions of iOS, the system would notify users of available App Store updates with a badge on the icon (seen above).
You had to open up the App Store, press the Update button, then press Update All. It was rather annoying to keep up with all the apps that needed updating. Sometimes by the time you finished updating, more apps would need updating.
Now with iOS 7, the apps will now automatically update. To make sure that the apps are set to automatically update, go into Settings and scroll until you see iTunes and App Store.