With the advent of Xorg 7.5 and XInput 2, applications are no longer restricted to the now old "1 pointer, 1 keyboard" interaction paradigm. Now the X server allows having an indefinite number of pointer/keyboard pairs, allowing for multiple input, be it either from multiple users, or from a single user with specialized hardware such as multitouch screens.

Paralelly, GTK+ has gained knowledge about multiple input devices through XInput 2 in an experimental branch. This talk will approach in a practical way the changes and concepts that application and widget developers should take into account when developing with several input devices in mind.