A free app for Android, by FlashLight.
Ultra GPS Logger Lite is a free, lightweight, open-source GPS Tracker app for Android that allows you to generate NMEA, KML, and GPX logs with your GPS or GLONASS-enabled Android device. The app can keep your GPS enabled for as long as it is in standby mode, allowing you to generate long-term logs without having to worry about battery life.
How does it work?
When logging, GPS Logger will use the location received from the GPS receiver and store it in a file. If you are tracking with a mobile device, you can run the program in a background process.
