How to completely quit an app on the iPad

Sometimes things go wrong and one way to fix it is to quit the app.

For iOS7 and later

For iOS6/iOS5
To do this, double-tap the home button to access the task manager. Press and hold on the unrealBook icon 
in the task manager until it wiggles. Then press the minus (-) sign to the left of the icon. This will quit unrealBook removing it from memory. Here is a link to a detailed explanation:

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