The original article, The Ultimate Guide to Solving iOS Battery Drain by Scotty Loveless, describes his experience as an Apple Store Genius. He describes the tests he was involved with and imparts some insider knowledge on battery drain on the iPhone:
Here are the highlights:
1. Turn off Location Services and Background App Refresh
So I tried disabling Location Services and Background App Refresh for Facebook, and you’ll never guess what happened: my battery percentage increased. It jumped from 12% to 17%. Crazy.
2. Stop swiping to close apps. Launching and quoting apps draws power as the app loads into RAM.
What most people tell you is that closing your apps will save your battery life because it keeps the apps from running in the background.
Yes, it does shut down the app, but what you don’t know is that you are actually making your battery life worse if you do this on a regular basis.