Hook up a door sensor (like https://www.adafruit.com/products/375) to a device that notifies a feed with its value. When the door is opened it will notify your phone!
If
Monitor a feed on Adafruit IO
This Trigger fires anytime it validates the data that you send to your feed. Example: If Feed Temperature > 80, fire Trigger.
Then
Send a notification from the IFTTT app
This action will send a notification to your devices from the IFTTT app.
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