The Arduino code takes all of the individual dialed numbers and combines them into a phone number. The sketch is set up so that after the 10th digit is read, the phone call is placed using an off ...

Adafruit has this week made available the Arduino FONA 800 that has been designed to provide Arduino development boards with the ability to enable Arduino cellular GSM via both voice and data.

The GSM Shield also includes a Telefonica SIM card that includes a worldwide data tariff which can be used anywhere there is a cellular signal.