Global Positioning System (GPS) telemetry technology has been a boon to animal spatial ecology studies. Oftentimes, the main limitation to widespread application of this technology is the cost, which can dictate the number of individuals outfitted with GPS technology, thereby limiting sample sizes. Here, we discuss the development of a low-cost, customizable, open-source hardware GPS logger for use in animal movement studies. We also present results from field tests with Eastern box turtles (Terrapene carolina) in northwestern Ohio. These GPS loggers have the potential to augment existing projects and facilitate studies that would be otherwise cost-prohibitive. Keywords: GPS, Data logger, Arduino, Eastern box turtle