On iPad it is possible to forcefully close any application that no longer responds to user commands by accessing the list of recently used apps. Swiping an application icon out of this list will close its program completely. If an application crashed during normal use of the iPad and stopped responding to commands, you can solve the problem by forcing it to close and restarting it. Any apps that cause constant problems or that you no longer need should be deleted to free up memory space on your device.
Steps
Method 1 of 3: Close an Application
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Step 1. Double press the Home button
This will display the list of all recently used apps.
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Step 2. Find the application you want to close
To do this, swipe the list that appears to the right or left.
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Step 3. Swipe the app icon or page up to permanently close it
It is also possible to close two applications at the same time using two fingers.
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Step 4. When done, press the Home button
This will redirect you to the home screen of the device.
Method 2 of 3: Force Restart a Locked iPad
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Step 1. Press and hold the "Sleep / Wake" and "Home" buttons at the same time
The "Sleep / Wake" button is located along the top of the iPad case and is used to turn the screen on or off. The "Home" button is located at the bottom of the screen, exactly in the center.
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Step 2. Press and hold the indicated buttons until you see the Apple logo appear on the screen
Before that happens, the screen will be completely turned off. Remember not to release the indicated keys until you see the Apple logo appear on the screen.
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Step 3. Wait for the iPad to complete the boot process
Once the Apple logo has appeared on the screen, you can release the indicated keys. At this point, all you have to do is wait for the start-up procedure to complete which should take 1-2 minutes at most.
Method 3 of 3: Delete an App
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Step 1. Press and hold the icon of any of the apps on the Home screen
After a few moments, all application icons should start vibrating.
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Step 2. Find the app you want to uninstall
While the application icons are animated, you can still scroll through the pages that make up the device's Home screen.
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Step 3. To delete the desired app, tap the "X" badge in the corner of its icon
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Step 4. When prompted, hit the "Delete" button
The selected application will be completely deleted from the device. You can install it again and at any time by downloading it again from the Apple App Store.