How to See What's Killing Your iPhone Battery

This morning my iPhone battery went from a full charge to completely dead in a little over four hours without me using it for anything at all. That's not at all what I expect from a smart phone that's doing little more than laying on my desk, so I wondered exactly what was eating all the juice in my iPhone's battery. Thanks to a tip TMO's own Melissa Holt wrote almost a year ago I was able to solve the mystery.

Apple added a new feature in iOS 8 that lets you see which apps are taking the biggest hits on your battery life, and as Melissa detailed, you find that by tapping Settings > General > Usage > Battery Usage. What I found was that Facebook was responsible for 82 percent of my battery usage over the last 24 hours—well above Tweetbot's second place slot at 6 percent. The salt in the wound for me was knowing I hadn't actually used Facebook on my iPhone in the past day.

Drat you, Facebook, and your battery-killing ways!Drat you, Facebook, and your battery-killing ways!

The Battery Usage view also gave me a hint as to what the Facebook app was doing when it sucked down my iPhone's battery so quickly: background activity. Thanks to that little clue, I shut off Facebook's background activity privileges by going to Settings > Facebook > Settings and turning off Background App Refresh. Now Facebook gets to check for new messages and other content only when I'm actually in the app.

Check out Melissa's awesome tip if you're having mysterious battery life issues on your iPhone, iPad, or iPod touch. She rocks, and so do her tips.