Mophie Juice Pack - iPhone Accessory Reviews by Mobile Tech Review

Mophie Juice Pack for iPhone

Reviewed May 20, 2008 by Tong Zhang, Senior Editor

Editor's note: Have an iPhone 3G? Check out our review of the Mophie Juice Pack for the iPhone 3G.

The first things that many iPhone users seek after getting their shiny phone are a case and an extra battery. We’ve seen some great cases and a few battery packs, but the Mophie Juice Pack combines a case and a battery pack in one with integrated Lithium Polymer rechargeable battery built into a hard slip case. It’s easy to use: just slide in your iPhone and start charging. Better yet, it doesn’t interrupt tasks like making phone calls, browsing, listening to music and more. The battery jacket looks slim by battery pack standards, but it does add some heft to the iPhone: you won’t want to hold the phone for a long conversation while in the Juice Pack (iPhone 4.8 ounces + Juice Pak 3 ounces= 7.8 ounces total weight). Note that this Juice Pack model is only for the original iPhone and not the iPhone 3G.

There's a gap between the bottom of the iPhone and the Juice Pack so the Pack doesn't block the iPhone's vents.

As a Case

It’s amazing what a bright color can do to improve a look, and the black Juice Pack inside surfaces are lined with a bright grass green that catches your eye. The jacket is sturdily built but feels smooth and soft. Two strips of rubber on either side of the jacket feel just slightly rougher than the case’s grippy soft touch body, and prevent the battery pack slipping from your hand. Measuring 2.5 x 4.75 x 0.75 inches, the Mophie Juice Pack adds very little to iPhone’s width, about half of an inch in length and about a quarter of an inch in thickness. The Juice Pack weighs 3 ounces and for that extra weight, you get doubled battery life for your iPhone. Not bad! The Juice Pack has an intelligent battery with 4 LED lights on the back to indicate power level. As a case, the mophie Juice Pack doesn’t protect the screen but is sturdy and protective in all other areas.

As a Battery Pack

We’ve seen several battery packs for the iPhone, all as USB battery sticks in one form or another with lovely wires to connect to your phone. The Mophie Juice Pack’s design is obviously cleaner. The built-in Lithium Polymer battery is 1800mAh in capacity, which is slightly higher than the Proporta Mobile Device Charger Micro but a bit lower than FastMac’s iV battery pack for the iPhone. The claimed runtime of the Juice Pack equals the runtime of the iPhone’s battery, which means you get double the runtime when you have full charges on both. Our tests showed that these numbers were very to close to target.

Since the iPhone doesn’t have a user replaceable battery, users are more concerned about not only the runtime per charge, but the battery’s long-term lifespan. The Mophie Juice Pack has a few tricks to avoid exhausting the iPhone’s built-in battery prematurely and unnecessarily. The Juice Pack incorporates Smart Battery Technology that not only charges your iPhone’s internal battery but also ensures the iPhone will use the battery power from the Juice Pack first. And once the battery runs dry, the Juice Pack will give you an audible alert and you can charge it with the iPhone charger. The claimed rechargeable cycles are 500, and we haven’t used it nearly long enough to comment if that’s accurate. The mophie Juice Pack counts only full charges as a cycle, this means if you only top off on power but don’t charge it all the way, it won’t count as a full cycle. The Juice Pack has a pass-thru charging connector, so when you charge the pack with the iPhone plugged in, your iPhone gets charged as well as the battery pack. The connector does not support syncing however. The iPhone charger fits fine, but the Juick Pack won't fit in the cradle.