How to control android app with arduino I'm trying to connect Arduino Leonardo to an Android tablet. I would like to make the Arduino send commands (using pushbuttons or a slider for example) to the tablet to switch between pages, to select a file on the desktop, to scroll up and down the screen, etc.  

Thanks. I will really appreciate your help.
Perhaps this is not exactly what you are looking for, but from your examples it seems like using navigational commands from the keayboard/mouse would accomplish a lot of what you are requesting. 

Android has USB HID support from honecomb, so you should be able to create a sketch to emulate a keyboard and mouse based on the IO data and it should work with your android device just by plugging the USB cable (if emulating a mouse, it will display the mouse cursor as soon as it is connected).