https://hackaday.com/2014/05/08/the-pebblypi-a-smart-doorbell/
The PebblyPi: A Smart Doorbell | Hackaday
May 9, 2014 - A Pebble smart watch, and a Raspberry Pi. They are a perfect match. This is probably what [Daniel] thought when he embarked upon his latest project, a smart...
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