The new iOS 9 has a feature called “low power mode” that claims to save battery life. The phone prompts you to enter this mode when your battery falls below 20%.
Low Power Mode seems to turn off notifications, and background activity, and reduces other battery-wasting features to on-demand only.
This is great for saving that last bit of battery on your dying phone, but I thought it would be useful to use it full time on a phone as well. So I tested it an older iPhone 5.
[](http://themainframe.ca/content/images/2015/09/iphone5-e1443229882881.jpg)This phone is on a different carrier than my regular phone, and I like to keep it around just in case my main phone is unavailable. I also let my kids borrow the phone when they’re going out somewhere, or when they need to desperately watch the new Zack Scott Games video. And since it uses a [7-11 Speakout SIM](http://themainframe.ca/tag/speakout/), it only costs a couple of dollars a month.
The phone doesn’t get a lot of use, and usually sits around on a kitchen counter. A perfect candidate for Low Power mode.
The phone has 455 battery cycles on it. It was my main phone for a while, then it was handed down to my wife before becoming the backup phone. Still, Coconut Battery reports it still holds about 89% of its original battery charge.
[](http://themainframe.ca/content/images/2015/09/Screen-Shot-2015-09-25-at-7.09.21-PM.png)I charged it fully, switched on Low Power mode and checked on it every day to see how it was doing. It lasted 5 days, with very light use — listening to podcasts, a bit of youtube, etc. In total, we used it for 4 hours, but it lasted for 120 hours on standby. Pretty good!
[](http://themainframe.ca/content/images/2015/09/IMG_0126.png)
I’m going to try low power mode on a new iPhone 6S this week, to see how long that battery would last under the same conditions.
