Please add the "Exit" button to the menu in the Android app.

On Android, it is not always clear if an application is closed by pressing the back button. The app can be accidentally minimized by the Home button and remain active.

Recently this situation happened: the Mnemosyne Android app was accidentally minimized instead of exiting. It was inactive for about 4 hours, and then, at about 3 am, it suddenly started working. A phrase in a foreign language from a dictionary sounded very loud. Everyone was scared!