Battery capacity?

Hey there, Carol!

First off, thanks for thinking of Swappa! Swappa's the best way to save money on a cheap iPhone for your grandchild.

As for which iPhone has the best battery life: Newer iPhones generally have longer runtime than older iPhones. Not only are batteries becoming higher capacity over time, but processors and screens have also become more energy efficient.

Apple officially rates the iPhone 7 and iPhone 8 to have 13 hours of battery life for continuous video playback. But batteries wear out over time, so an iPhone 8 may not have quite the same endurance today as it did upon release. Many sellers post the battery health percentage in their listing text or images. But if they don't, you can leave a comment on the specific listing you're looking at, asking the seller about the battery health!

Note: Apple's larger "Plus" models (iPhone 7 Plus and iPhone 8 Plus) don't cost much more and have bigger batteries and are rated for 14 hours of continual video playback.

However, I would recommend stepping up to the iPhone XR. Not only would this be a newer and faster iPhone that can keep up with the latest apps for longer, but you also get a dramatic increase in battery life (officially rated at 16 hours of video playback).

Visit the Swappa blog to find out which iPhones have the best battery life and what you can do to optimize the battery life of whichever iPhone you choose!