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The common truth with phones is that as the design gets thinner, the battery life shrinks. The iPhone 12 family is no different — 12 Mini, 12, 12 Pro and 12 Pro Max included — and on intense days with FaceTimes, lots of typing and gaming, the battery percentage can drop quickly.

So what’s the fix? Traditionally, it’s a portable battery pack that you plug in or a battery case that snaps onto your phone. The new solution is the $99 MagSafe Battery Pack, which attaches to the back and wirelessly charges your iPhone. And we’ve spent several days with the MagSafe Battery Pack, using it on the entire iPhone 12 family. Let’s let lightning spark and unpack the latest iPhone accessory.

Designed for the iPhone 12 Mini, 12, 12 Pro and 12 Pro Max

If you want a purpose-built battery that doesn't add much weight and brings a ton of function, we'd say the $99 MagSafe Battery Pack fits the bill.

The who, what and how

Who this is for: The MagSafe Battery Pack is a purpose-built accessory that takes advantage of the iPhone 12 design and aims to stretch the battery life a bit more. It’s ideal if you don’t want to be bothered by carrying a separate portable charger.

What you need to know: This accessory gives iPhone 12, 12 Mini, 12 Pro and 12 Pro Max users a simple and engaging way to extend battery life. Moreover, it integrates with iOS in a way that other batteries or options can’t. However, it’s not the longest-lasting or fastest charger out there.

How this compares: Apple’s MagSafe Battery Pack is neither the thinnest nor the fastest portable charging solution. Traditional battery packs might be larger and a whole separate device, but they offer more mAhs and ports, which let you charge more devices. Third-party solutions — like Anker’s or Hyper’s magnetic power banks — still easily attach to the back but don’t offer the software integration and slim designs. Often, they’re larger and produce a bit more heat when in use. No other portable battery offers deep integration with iOS, though. The MagSafe Battery Pack is firmly an extender that won’t fully recharge an iPhone but offers convenience and a few neat tricks for $99.

Snaps to the back

The MagSafe Battery Pack is centered around power and design, the latter of which takes unique advantage of Apple’s MagSafe technology. This Battery Pack quickly snaps to the back of the iPhone 12 Mini, 12, 12 Pro or 12 Pro Max. Magnets built into the back of the iPhone match up with magnets on the battery pack itself. And it snaps with a satisfying thud on the back.

Like Apple’s Smart Battery Cases, this accessory will create a hump on the back of your phone. The MagSafe Battery Packs measures in at about 11 millimeters thick and weighs in at 113 grams. That’s smaller than the original iPhone and close to the size of a MagSafe Wallet. It’s a hard shell plastic design that comes only in white with a gray Apple logo centered at the top. Previous Smart Battery Cases have opted for a soft silicone shell, but this harder plastic seems better against denim and drops. Namely, it doesn’t scuff as quickly and doesn’t show dye from jeans after some early tests.

The bottom of the MagSafe Battery Pack features a Lightning port and a single LED indicator that lets you know when it’s charging. You won’t find a Lightning cable included in the box, though you’ll need one to charge the battery pack. Here’s the best Lightning cable of 2021. When you plug the Battery Pack into a Lightning cable for charge, the LED indicator will glow orange for a bit, and green when it’s fully charged. We imagine Apple opted for the Lightning port as you already have that for the iPhone it will be attached to.

Now, regardless of your iPhone — 12 Mini, 12, 12 Pro or 12 Pro Max — you’ll get the same MagSafe Battery Pack. It’s a one-size-fits-all approach. On an iPhone 12 Mini, it covers the bottom back, matching perfectly with the edges. On the 12 or 12 Pro, you have some more wiggle room on the left, right and bottom. With the 12 Pro Max, it sits centered on the back with plenty of space. The bigger the iPhone, the more back room.

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So it’s a small hump on the back that, while noticeable, isn’t obnoxious. The iPhone 12 or 12 Pro is still easy to hold with the MagSafe Battery Pack on and it makes the 12 Mini easy to cradle. We’re also happy to report that it still fits in our skinny jeans front pocket. The magnet provides a strong connection that we haven’t been able to knock off by waving our phone around or sliding in and out of spaces like jeans.

There’s nothing truly fancy here, though we can’t help but wonder why Apple didn’t offer this new accessory in other colors. A MagSafe Battery Pack color-matched to a purple iPhone 12 or blue 12 Pro would have been delightful.

It’s an extender, not a super-fast portable battery

The MagSafe Battery Pack isn’t competing against traditional portable batteries or fast chargers. It’s best thought of as a battery extender. When you have a long day where the iPhone 12 needs to go the extra mile, you can attach the MagSafe Battery Pack and get a charge going.

Apple doesn’t typically share many specs, and with the MagSafe Battery Pack, the company initially didn’t state the battery size. The rear of the battery pack reveals the cell inside: a 1,460mAh (11.3Wh). Both numbers relate to total capacity, but the Wh is close to that of an iPhone 12 or 12 Pro, so we’d imagine it’s not a small 1,460mAh cell inside but potentially two of them. Apple’s charge rate here is faster than alternatives from Anker ($45.99; amazon.com) or Hyper ($39.99; hypershop.com), which feature bigger cells and a cheaper price tag.

And after nearly a week of testing, you can expect the MagSafe Battery Pack to deliver around 60% of power to the iPhone 12 or 12 Pro. With the iPhone 12 Mini, that percentage is higher, and on the 12 Pro Max, it’s slightly lower. It’s firmly an extender here, though, and the amount of power you’ll get will vary depending on what you’re doing on the iPhone while charging. With the MagSafe Battery Pack just attached to the iPhone, it wirelessly charges at a relatively slow 5 watts. This is both to conserve battery health and for heat. And having it connected doesn’t generate a tremendous amount of heat either. It’s similar to the level of warmth that a Smart Battery Case delivers.

For instance, being on FaceTime or playing a game is more taxing on the battery and the charger, therefore you won’t see a real-time wild jump, especially at 5 watts. We attached a fully charged MagSafe Battery Pack to a dead iPhone 12, and after an hour of charging, it hit 46% with about 25% battery left in the pack. That’s pretty great. During a long workday, we attached the MagSafe Battery Pack before our commute home to ensure we’d have enough battery life. On a regular night, we’d end with about 15% to 20%, and we left with 30% to 40% while using the device for streaming and communication while commuting home. So, yes, the charge varies, but it’s an extender when just attached to the back.

If you have the MagSafe Battery Pack plugged in with a cable while it’s attached to the back of your iPhone 12, the charging speed zips up to 15 watts. That’s a much faster standard that the MagSafe Wireless Charging Puck can produce. It’s pretty handy as well since the MagSafe Battery Pack is dual purpose; you can use it to keep the iPhone going while on the go or have it plugged in on your desk in a wireless charging capacity.

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What’s really cool is that if you have your iPhone 12 Mini, 12, 12 Pro or 12 Pro Max plugged in with the MagSafe Battery Pack attached, the phone will charge the pack as well. This is done through reverse wireless charging, and it’s the first time this capability has been unlocked on the iPhone. It’s similar to how the Pixel 5 or a Samsung Galaxy can charge a pair of earbuds or another Qi-enabled device off the back. This charging feature is a pretty neat bonus.

Alongside a simple design and extra battery life, the $99 price tag also affords some convenience. The MagSafe Battery Pack is integrated with iOS in a way that no other battery pack can be. Similar to what happens when you connect a MagSafe wallet or case, the MagSafe Battery Pack flashes a graphic and the battery level of the pack once you connect it. The battery indicator in the top right corner of iOS will glow green when it starts to receive power. As soon as it’s attached, it will begin delivering power to the iPhone. You will need iOS 14.7 to take full advantage of all the MagSafe Battery Pack has to offer.

Bottom line

Like previous Smart Battery Cases, it’s all about the convenience here — not the size of the battery. You can get much larger batteries for less than the MagSafe Battery Pack’s $99 price tag, but they don’t snap to the back of your phone in an instant or integrate with iOS. You can monitor the battery life of the pack right in a widget, and the iPhone can push power to the MagSafe.

If you want a purpose-built battery that doesn’t add much weight and brings a ton of function, we’d say the $99 MagSafe Battery Pack will help you cross that finish line at the end of a busy day. It’s not an endurance charger, though. Those looking for a purely larger amount of power should look at Hyper’s or Anker’s magnetic packs.