Here's how to close an app that has crashed in iOS 5 without having to reset your device. 1. Go to the Home screen. 2. Double tap the Home button to bring up the App Switcher. 3. Find the icon for your crashed app and press until you see a minus sign appear in the upper left corner. 4. Tap the minus sign to close the app. 5. Relaunch the app from the Home screen. This is a fast and easy way to deal with frozen or crashed apps in iOS 5. It should work for your iPhone, iPod Touch or iPad.
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iOS Tips and Tricks | Tech Crunch