What wireless device and app to report to iPhone that freezer door has been left open

By Kate from UK, 15 November, 2017

Forum
Apple Hardware and Compatible Accessories

Is there an accessible app to send me a notification that I've left the freezer door open? I need the time delay to be choosable, don't want a notification each time I open the door. I've seen a time-delay piece of kit which will sound an alarm after user-defined time if door open, but not sure if I'd hear it as freezer in garage.

Options