Arduino Uno project to send SMS using A7670C GSM module and AT commands. - Releases · TilakChitagi/Arduino-GSM-A7670C-SMS-Sender ...

Teltonika SMS Relay with modem rotation. Contribute to pdvro/gsm-relay development by creating an account on GitHub.

Of course, we’ve seen GSM and cell phone shields for Arduino before. Difficult to imagine sticking those in a dog collar, though, unless you have a fairly large dog.