To set up a countdown to a claimed device, tap the "three vertical dots" icon to the right of the device, or swipe from right to left on the device.
Tap the "timer" icon to the left.
Slide the hours and minutes sections to set the length of your countdown.
Select "On" if you want your device to turn on, or "Flash" if you want it to flash when the countdown finishes.
Tap "Start" to start your countdown.
Your countdown will now begin and run in the background so you may use other applications or exit the app. Once your countdown is complete, your device will perform the assigned action.