This iPhone battery case is one of the strangest on the market, but also one of the best

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AmazonThe iPhone 6s’ battery life is fine. Not great, not bad, just good enough. The iPhone runs fast, and it looks great, but Apple’s insistence on slimness means that the battery within its devices can’t be too big. It does what it can to mitigate that, but it’s a trade-off. All of this applies to the iPhone 6, too, and it’ll probably apply to the iPhone 7.

There are ways around this, though. You could simply practice better habits. Or you could carry around a trusty portable battery. For some, though, the most convenient solution is to blend that spare battery with a case. That’ll fatten up all the work Apple’s engineers put into your phone, but it’ll ensure your phone stays alive longer, and add a modicum of scratch and drop protection along the way.

If that’s a trade-off you’re more willing to accept, the Prong iPhone 6/6s PWR Case should be on your shortlist. At $99, it’s expensive, but that’s partly because it’s one of the most versatile iPhone 6/6s battery cases on the market.

Like past Prong cases, the PWR’s most immediate aspect is the pair of foldable wall plugs built into its back. They’re jarring at first, but they’re integrated well, and they make it so you can charge the case and phone directly from a wall outlet, without the need for any cables or additional hardware. So if you’re, say, at work, and you don’t have a microUSB and/or Lightning cable handy, you have an additional way of ensuring you have power. Four helpful LED lights let you know when you’re close to full.  

The PWR’s battery comes in at 2,600mAh, which isn’t massive for the money, but is enough to virtually double an iPhone 6s’ battery life. For most people, that should be plenty, but you’re mostly paying for the feature set here.

The other highlight of that feature set is the fact that the PWR splits into two parts — if you know you won’t have to charge anytime soon, you can remove the battery- and prong-holding portion, and carry around the separate, much more lightweight case in which the iPhone actually sits. When you need more power, you just connect the case-bound phone back to the battery’s Lightning connector.

This means you don’t have to stuff a big lump in your pocket whenever it’s not needed. It helps, partly because the lighter case fits well in its own right, and partly because the PWR is fairly big when everything’s attached. That said, it is nicely smooth to the touch, and it does come in a few separate colors.

The PWR’s calling cards won’t appeal to everyone, and there are certainly better values out there. (The Anker Ultra Slim Extended Battery Case chief among them.) If you can afford to pay for a case that’ll charge your iPhone wherever you go, though, it’s a worthwhile investment.

Prong PWR iPhone 6/6s Battery Case, $99, available at Amazon.