I require an app to run on a car mounted 7 inch tablet which starts a timer when a switch on the vehicle is in a certain position. This timer is to countdown from a user defined value, between 1 hour and 4 hours, and after counting down, if the switch has not changed, the tablet is to initiate a phone call to a user defined phone number or email or sms. Basically, some form of contact to alert the owner that the switch is in the wrong position.
This app requires an external trigger, possibly from a usb keyboard which has been hacked or arduino.
Have just discovered the app Tasker so can solve this one myself.
Many Thanks to all who have got back to me.