OpenTracker is the only professional GPS/GLONASS vehicle tracker released open source under the GPL v2 license.
Powered by a 32-bit ARM microcontroller, OpenTracker is natively supported by the Arduino IDE, taking advantage of the vast Arduino code base.
The default software includes many advanced features such as real-time tracking, geofencing, analog sensors, CAN bus, battery monitor, external commands, audio, SMS, and many others. It works right out of the box as vehicle tracker; the only requirement is a SIM card.
OpenTracker hardware features include quadband 2G or 3G modem for wireless connectivity, GPS/GLONASS receiver with Assisted-GPS, plenty of digital and analog I/O, CAN bus, USB, audio interface, expansion interface with SPI, I2C, UART, GPIO, ADC. Its extended temperature range (-35°C to +80°C) and voltage range (9V to 36V) makes it ideal for installation in vehicles, heavy machinery, industrial sites.