Here's how the new battery usage monitor works in iOS 8

iOS 8 brings something similar to OS X Mavericks-style battery usage — aka battery shaming — to the iPhone and iPad. Located in the Settings, General, Usage section, it tells you which apps and system services are using power, and how much. Obviously the ones using the most power are doing something wrong and should be shut down, right? Wrong. Like many things, the answer is far more complex and nuanced than simple power bad, quit good. So, what does iOS 8 battery usage really mean and how should you use it?

Battery usage is best thought of as a sanity check. It lists each app (or service) you've used in the last 24 hours or 7 days, not including apps used while charging, along with the percentage of power drain they've been responsible for.

There are at least four reasons why apps will use a lot of power:

  1. You used the app a lot. (Messaging, reading, watching, etc.)
  2. The app remained active in the background a lot. (Downloading content, streaming audio, providing location, etc.)
  3. Poor signal strength or some other technical issue affected performance.
  4. The app misbehaved.

Reason 1 is nothing to be concerned about. You're using power because you are using power. You're Tweeting or surfing, or streaming the latest season of Arrow or otherwise keeping the screen on and the radios working. That's what your device is for. So, if you've spent an hour in Tweetbot or Safari or Netflix and they're top-of-the-list, that's fine. If you've been rearranging your folders and Home screen is up there, that's fine. As long as you've been using it, it's fine if it's there.

Reason 2 is likewise the result of proper activity. If you'd rather have extra battery life, you can turn off background refresh, turn off location access, or kill audio streaming, but you'll have to wait longer for new content when you open apps, you'll disrupt navigation and checkin apps, and you'll lose out on listening to internet radio, podcasts, and more.

Reason 3 is because of things like low phone signal, which means the cellular radio needs more power to connect. If that's the case, the Phone app will appear there and list low signal as the reason, making it easy to understand. Poor Wi-Fi performance can likewise cost power though I've yet to see it noted in battery usage. Likewise, firing up the GPS for turn-by-turn navigation is a huge drain I've yet to see noted.

Reason 4 is where battery usage shines. Let's say you go to battery usage and see Google Hangouts, Facebook, Skype, etc. near the top of the power consumption list, and you find it strange because you haven't been using them. That's when you know there's a problem and that you can likely do something about it, be it quitting the app or rebooting the device.

Again, if Tweetbot or Twitterrific is at the top, and you've spent much of the day tweeting, you have no problem. If Hangouts or Facebook is at the top and you've barely opened them all day, then thanks to battery usage, you now have a potential solution!

There are a couple of important things to remember before you get too busy with battery usage, however. First, a usage percentage is just that. If your iPhone is at 80% but YouTube used 50% of that, that's still only 10% of your power. Do the math before you panic.

That's why battery usage should be an occasional tool, not a frequent obsession. Only check when and if you suspect you're draining power faster than normal, and then only take action on apps you suspect are causing that drain for no legitimate reason.

With great power stats comes great responsibility, so check out battery usage on iOS 8 and tell me how it works for you!

Rene Ritchie

Rene Ritchie is one of the most respected Apple analysts in the business, reaching a combined audience of over 40 million readers a month. His YouTube channel, Vector, has over 90 thousand subscribers and 14 million views and his podcasts, including Debug, have been downloaded over 20 million times. He also regularly co-hosts MacBreak Weekly for the TWiT network and co-hosted CES Live! and Talk Mobile. Based in Montreal, Rene is a former director of product marketing, web developer, and graphic designer. He's authored several books and appeared on numerous television and radio segments to discuss Apple and the technology industry. When not working, he likes to cook, grapple, and spend time with his friends and family.

  • Gotta be in it to win it! Sent from the iMore App
  • Do it to it!
  • Shooby-dooby-doo-wop!
  • You've said it's similar to Mavericks. How? I can't seem to find out what drains my rMBP in 2 hours while I'm just using safari. ( I am running Yosemite which might explain it.) but I definately want to figure out how to check what apps are using battery. Sent from the iMore App
  • Go to activity monitor and check power usage. It's probably safari networking process or something like that. Sent from the iMore App
  • Mouse over the battery icon in the menu. While unplugged, it will show you "Apps using significant energy". If that's Safari I'd bet on Flash being an issue - Flash ads, etc. You can either uninstall Flash entirely (a lot of video is HTML5 so that works well) or use an extension like Flashback that suppresses Flash, letting you click on Flash objects if you want to see them.
  • My solution to the POS Flash issue: uninstall Flash (or better — don't install it in the first place), and use Chrome when you encounter web content that still demands Flash. Chrome has sandboxed Flash Player built into the browser, and it updates itself with Chrome updates — which means no more incessant, annoying f*cking update nags from Adobe, among many other benefits. There's even an Alfred workflow that will send the current URL in Safari to Chrome, when you encounter Flash-only content...instead of copy-pasting the URL. I'm not a fan of Chrome, other than for this very convenient “feature”.
  • Awesome. Thanks. I'm not a fan of chrome either but just using it for that sounds like a great idea. Sent from the iMore App
  • Thanks for the advice I'll check that out. Sent from the iMore App
  • As always, great article Rene! Good job... Sent from the iMore App
  • Thanks for the article. One issue: the "do the math" passage (80% left, 50% used of 20%) doesn't quite work because the per-app percentage is a choice between "Last 24 Hours" or "Last 3 Days", not "Since Last Full Charge".
  • It might have been more helpful if they had included battery usage over time instead of just a flat percentage.
  • I think you mean soft reset. Great for :)
  • Actually, it is a hard reset. A forced reboot w/o software assist.. like hitting a reset button on a desktop of old... Not as safe as pressing power to shut down and reboot because you could loose anything you have actively going... Soft reset it remembers what apps were going. You maybe thinking of hard reset as a wipe that erases data.
  • ah. yes I was.
  • Great tips Rene! Was wondering about the battery usage monitor.. I think that should be an optional widget in notification center!
  • AAAAAAARRRRRRRRGGGGGGGGHHHHHHH Flipping up an app DOES NOT SAVE POWER! That is simply a system to allow you to reenter an app where you left off. Nothing is running in the background! Would you people STOP incorrectly informing people of that.
  • is there a way to actually stop an app?, I dont have safari running but its using 70% of my battery?
  • This is actually pretty rad. I am getting great battery life with mine, though admittedly, I do not allow a lot of background refreshing, apps running and whatnots.
  • Rene, the Phone doesn't necessarily appear if there's usage in Low Signal areas. 'Low Signal' simply indicates that the app (it can be any app, not just the Phone) drew a lot of power because YOU used it in low signal areas.
  • I'm going to try to follow the advice on not to check it regularly but I know I'll fail... at least the first few days.