Trackers for runaways

My girl broke her lead a little bit ago, and went for a walk while I was fixing her dinner. She did come back when I called her, but that is a rare occurance. I'm wanting to get a GPS tracker, but don't know what good ones are available that are reasonably priced and reliable. I was looking at Jiobits but they're fairly expensive and I'm not sure how well their GPS capabilities actually are.

Any advice? Suggestions? All appreciated.