Field Day is labeled a "high battery usage" app on some devices
The Asus tablet and Craig's Samsung phone (at least those two devices; check on others as part of fixing this issue) report Field Day with a tag of "Battery usage: high" in the "Location" menu. Investigate energy usage and fix.
Initial issue description:
The Asus skin has some power management built-in, when field day has been running for a while it is labeled as a "Battery-draining app". Figure-out why and fix it.