Remote Mouse - Turn your smartphone into a wireless touchpad and keyboard now!
Mac Mouse Fix - A simple way to make your 3rd party mouse better.
KDE Connect - Integrate Android with the KDE Desktop
Smooze - Smooze animates your scroll and adds functionality to your non-Apple mouse (scroll-wheel mouse).
Monect - Make the best use of sensors on smart device to control PC, simulate steering wheel, game-pad...
libtwo - All-purpose c++ app prototyping library, focused towards live graphical apps and games