Remote Mouse - Turn your smartphone into a wireless touchpad and keyboard now!
SendRecurring - SendRecurring allows you to setup, send, and maintain scheduled email reminders.
KDE Connect - Integrate Android with the KDE Desktop
Recurrr - Send recurring emails
Monect - Make the best use of sensors on smart device to control PC, simulate steering wheel, game-pad...
Followup.cc - FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.