Useless Invention №58: Ball that predicts the next action of the Back button on Android devices. Will switch to the previous page; will reset all content on a dynamic page; will close the tab; will cancel an action in the app; will switch to the previous app; will minimize all apps; will switch to the main app window; will switch to a window a level higher; will minimize the keyboard; will display the popup menu; will minimize the popup menu; will do nothing.