Remote Mouse - Turn your smartphone into a wireless touchpad and keyboard now!
Macro Deck - Use smartphone as macropad for pc
KDE Connect - Integrate Android with the KDE Desktop
TouchPortal - Touch Portal is a companion app to control a PC or a Mac by using a deck of buttons to improve the workflow & productivity of game streamers, content creators and professionals.
LEA Extended Input - iOS/Android app with windows server to control functions in games via your smartphone/tablet.
Mobile Air Mouse - Mobile Mouse is the ultimate Remote & Trackpad for iPhone, iPod, iPad, Apple Watch, and Android.