i've made simple gps tracker based on arduino. it can write track into GPX format
Track file is stored in the folder named by the current date, and file name is start tracking time
Gps module controlled with TinyGPS library
Gps points stores every 1 second
Keep in mind that you should use dc-dc to 5v step up module to use 18650 barttery
sketch is attached
trevizan made it!