Footfall-GPS polling scheduler for power saving on wearable devices

Wrist-worn wearable fitness devices, such as FitBit and Apple Watch, have become popular in recent years. Runners can use the GPS embedded in these wearable devices to log the route taken during their exercise, providing vital feedback on pace and distance traveled. Unfortunately, continuous polling for GPS data results in a significant adverse impact on device battery life, e.g., many flagship wearables need to be charged as frequently as every two days or even less. In this work, we propose Footfall-an intelligent GPS scheduler that can utilize data from alternative sensors on a device to greatly reduce GPS utilization while still maintaining minimum location accuracy. Compared to existing implementations, Footfall system can achieve on average 97% reduction in total power consumption, while only inducing 7% discrepancy in location accuracy, which is sufficient for the targeted applications.