Swift : Information leak when entering background mode

Perhaps, the application does not override the default behavior when entering background mode. This may lead to valuable data leak.

When moving to the background mode, iOS takes a screenshot of the application. If valuable data was presented on the screen at the moment (for example, the user was entering a credit card number), its confidentiality may be violated. It is recommended to override the applicationDidEnterBackground method and replace the image on the screen with a predefined safe one.