Meet the Spark Electron: an Arduino like development kit for creating cellular-connected electronics. It comes with a SIM card and an affordable data plan for you to get started. The circuit board is about the size of your thumb and has a microcontroller and a cellular modem.
Here are the specs:
- STM32F205 ARM Cortex M3 microcontroller
- 1MB Flash, 128K RAM
- Cellular modem: U-Blox SARA U-series (3G) or G-series (2G)
- 36 pins total: 28 GPIOs (D0-D13, A0-A13), plus TX/RX, 2 GNDs, VIN, VBAT, WKP, 3V3, RST
- Board dimensions: 2.0″ x 0.8″ x 0.3″
These guys will provide you with SIM cards and manage the relationship with carriers and towers. Now that sounds intriguing. The cellular plan costs $2.99/month for 1MB (20k messages per month). Like what you see? You can find this product on Kickstarter.