Apple iPhone 3G or 3GS owners looking to extend the time they can chat, Web surf, check e-mail, and indulge in the myriad activities that their device allows them to do, will want to turn an eye toward the Mophie Juice Pack Air, a $79.95 battery and protective case that gives your iPhone an extra shot of life. The two-piece design is somewhat awkward, but, overall, we like this svelte spare tire that you can always keep attached to your iPhone.
The Juice Pack Air is made of a shiny, black plastic (also available in purple or white) that attracts fingerprints and smudges. Unlike other chargers we've reviewed recently, the Juice Pack Air comes in two pieces that encase your iPhone. To mount it, you snap off the top section that protects the uppermost portion of the iPhone, slide your device into it, then reconnect the two pieces.
The upside is the Juice Pack Air's snug, inconspicuous fit makes it seem as though you don't have a charger attached. The downside is that if you lose the top portion, the charger looks incomplete. Our main gripe with the design, however, is the Juice Pack Air's flimsiness: It feels as though it would crack with a modest amount of pressure. When attached to our 4.7-ounce iPhone, the pair weighs 7.0 ounces.
The back of the Juice Pack Air features a Power switch and four LEDs to monitor the charge level; four lights indicate a full charge, and one light means that the battery is nearly depleted. Similar to the Case-Mate iPhone 3G/3GS Fuel and FastMac TruePower iV, you can turn on the Juice Pack Air to deliver juice to your cell when you need it.
If you connect a fully powered iPhone to the Juice Pack Air and turn on the battery, Mophie's Smart Battery Technology instructs the phone to drain the Juice Pack first, leaving your phone's battery fully charged as long as possible. On our tests, the battery indicator on the charger lowered over time, while our iPhone 3G stayed charged after we disconnected it.
For the iPhone 3G, Mophie rates the Juice Pack Air to deliver 11.3 days of standby, 4.5 hours of 3G talk (9 hours for the original iPhone), 20 hours of audio playback, and 6 hours of video playback. An included microUSB cable let us charge the device to full capacity in approximately 90 minutes. When we connected the Juice Pack Air, the iPhone became operational within 6 minutes; that's not bad, although other chargers such as the RichardSolo 1800 and FastMac TruePower iV took only a minute to bring our handset back to life. The device itself charged in 2 hours and 10 minutes, which was swifter than the Case-Mate (2 hours and 30 minutes) and RichardSolo 1800 (4 hours and 50 minutes), but slower than the Fastmac TruePower iV (1 hour and 50 seconds) and Energizer Energi To Go Power2 (1 hour and 57 seconds).
Similar to the other chargers, the Juice Pack Air fully charged our iPhone 3G in just under two hours. After draining our phone, this accessory was able to bring it back up to 50 percent before conking out. That's in line with two other chargers we've tested (the RichardSolo 1800 and Case-Mate iPhone 3G/3GS Fuel), and better than the Energizer Energi To Go (which provided only 1.25 charges). The FastMac TruePower iV, however, delivers nearly three full charges.
At $79.95, the Mophie Juice Pack Air runs neck and neck with the Case-Mate iPhone 3G/3GS Fuel, in both price and performance. Some may prefer the Case-Mate's sturdier design, which includes a holster, but we recommend the Juice Pack Air for its low profile, which makes it convenient to keep this charger attached at all times.