Lately (ever since installing Pokemon Go, I believe) the App Store has been number one on battery usage. In the past 24 hours it has run 2 min on screen and 8.9 hours in the background. I have no apps that need updating and it's set to only update while on Wifi. I have tried logging out of the store and back in, rebooting the phone (home and start button), etc. Any ideas on what I can do?