Here is an updated tutorial for setting up a Raspberry Pi GPS Tracker in an even simpler, more reliable way with less hardware! You just need a Raspberry Pi 2 with Jessie and an Adafruit Ultimate GPS Breakout.

Full, detailed tutorial found on our GitHub Wiki

Hardware Wiring:

Pi 5V GPS VIN
Pi GND GPS GND
Pi UART_TX GPS RX
Pi UART_RX GPS TX
Software:

pip install pynmea2
pip install ISStreamer
sudo sed -e s/console=ttyAMA0,115200//g -i .backup /boot/cmdline.txt
sudo systemctl disable serial-getty@ttyAMA0.service
sudo reboot now
git clone https://github.com/InitialState/rpi-gps.git
cd rpi-gps
printf « [isstreamer.client_config]\naccess_key: YOUR_ACCESS_KEY » >> isstreamer.ini
python app.py

Full, detailed tutorial for building a Raspberry Pi GPS Tracker

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