We do just about everything with our iPhones, whether it’s gaming, HD video recording, browsing the Web, or making calls. We’re no strangers to battery issues with iOS 5 and ways to combat them, but it would be great if we didn’t have to worry about our phones dying on us at a crucial moment. Thankfully, there is the Mophie Juice Pack Air ($79.95), which roughly doubles your iPhone’s battery life.

Mophie’s battery cases have been around for some time, but if you haven’t heard of them, the Juice Pack Air is a two-piece battery case for your iPhone. You slide your phone into the bottom piece, which connects to your iPhone’s dock connector, then pop in the top piece. The case uses a micro-USB port to charge the 1500 mAh battery. Pressing a button on the bottom of the case activates one to four LEDs to indicate how much the case is charged. When you don’t want the case to charge your phone, simply flip its standby switch to red.

I’m a heavy data user when I’m not at home with the comfort of Wi-Fi. I mean, I’m the kind of user whose data speeds AT&T throttles with over half a month left on the billing cycle. On a typical day, my battery drops to 20 percent within four to six hours of near-constant 3G web browsing, texting, and tweeting. Over the course of a few days, I put the Juice Pack Air to the test. I avoided wall and car chargers throughout each day, relying only on the Juice Pack Air to keep my phone going.

The Good

The case itself is very nice looking. I’m using a white case with my white iPhone, and you can barely tell it’s there (other than the rounded back). The case also has a built-in acoustic chamber for the speaker to increase your device’s volume. As for the battery, it does its job very well. From leaving home at the start of the day, the Juice Pack Air kept my phone alive long enough to get home well after dark and still had some juice to spare. While the case didn’t ever provide a full charge from 20 percent, it consistently got me back to 70-80 percent once activated. Keep in mind, I was still browsing the Web every few minutes while the case was charging my phone.

The Bad

Since the case uses a micro-USB cord to charge, you must use that same micro-USB to USB cord to charge and sync your iPhone while it’s in the case. This shouldn’t be a problem for most people, but if you dock your phone, then it might become a hassle.

Verdict

Mophie’s Juice Pack Air is a must-have accessory for the iPhone power user. It does what it’s supposed to while providing some peace of mind from your iPhone dying when you need it most. In my testing, the Juice Pack Air met all my expectations. This would be great for anyone who records a lot of video, uses their phone as a mobile hotspot, or uses location-based apps often.

For more color options, detailed specs, and ordering information, visit Mophie. Would a battery case be beneficial to you? Or, do you take your wall charger wherever you go?