Remote Mouse - Turn your smartphone into a wireless touchpad and keyboard now!
DisplayFusion - DisplayFusion will make your multi-monitor life much easier.
KDE Connect - Integrate Android with the KDE Desktop
Mizage Divvy - Divvy is an entirely new way of managing your workspace.
Monect - Make the best use of sensors on smart device to control PC, simulate steering wheel, game-pad...
WindowGrid - Quickly and easily layout windows on a dynamic grid using just the mouse.