Wanderlog - Collaborative travel planner with combined itinerary and map
Remote Mouse - Turn your smartphone into a wireless touchpad and keyboard now!
Scout - Scout ♥ monoliths.
KDE Connect - Integrate Android with the KDE Desktop
PlanMoreTrips - Github for travel planning - no more spreadsheets!
Monect - Make the best use of sensors on smart device to control PC, simulate steering wheel, game-pad...