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In Android applications, it is very common for users to use the physical back button on the device itself, instead of a back button on the screen.
PhoneGap Apache Cordova uses an event listener called "backbutton" to catch when a user presses the Android back button. The prepackaged PhoneGap Apache Cordova Android project in Profound UI already handles this event and looks for the app to handle it in the Rich Display File simply by including a button with the id of "btnBack". The button can be hidden on the screen if desired.
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