As we’ve mentioned in previous reviews of iPhone batteries, there are considerable advantages and disadvantages to backpack-styled iPhone power cells: they’re generally the easiest to carry around and use, but also tend to be more expensive, and are not guaranteed to work with any future iPhone model or other Apple device, such as iPods. Today, we look at two different iPhone battery backpacks: PhoneSuit’s MiLi Power Pack for iPhone ($80), and Mophie’s Juice Pack for iPhone 3G ($100).
Price aside, it’s actually interesting to note how much these two batteries have in common. Both contain 1800mAh batteries, which the companies indicate will fully recharge the iPhone 3G once and have a little extra power left to spare, using four blue LEDs and a power indicator button to display the remaining charge. Each comes with nothing more than the battery accessory and a USB cable for recharging, though PhoneSuit presently offers a free screen protector pack with MiLi. And both have a neutrally colored exterior with a slightly visible, brightly colored interior lining. Juice Pack is sold in a black matte soft touch rubber finish with a soft touch green interior, while our MiLi came with a glossy black exterior and a bright blue interior.
The differences continue in the cosmetics. MiLi is actually offered in six versions, half glossy black and half glossy white, each with green or gray inner linings, and the white one with orange instead of the previously mentioned black and blue version.
It’s also a bit taller than the latest Juice Pack, adding 3/4” to its height rather than Mophie’s 1/2”; both roughly double the iPhone 3G’s thickness.
Functional differences are also noteworthy. Whereas Juice Pack is solely designed to work with the iPhone 3G, and doesn’t connect to the original iPhone, MiLi works with both. PhoneSuit has placed MiLi’s battery indicators and button on the unit’s bottom front rather than on its back, where Juice Pack’s are located, and MiLi also includes an outgoing full-sized USB port in addition to the incoming mini-USB that both it and Juice Pack situate on the bottom left corner. As a result, Juice Pack does one thing: it recharges the iPhone 3G. MiLi recharges the iPhone, iPhone 3G, and also any other USB device you might want to connect to its bottom. The only other backpack to offer a similar feature was FastMac’s TruePower iV.
Another functional difference worth noting is speakerphone performance.
Backpack-style batteries unfortunately have to choose either to obscure the iPhone’s bottom-mounted speaker and microphone, or find smart ways to pass the audio through without creating echoes. Callers told us that we and they sounded better through Mophie’s design: there was only the feintest echo on occasion when they spoke, and slightly clearer sound when we spoke. With MiLi, they reported that our voice sounded a little compressed with what appeared to be faint static in the background, and a distracting echo of the caller’s voice could be heard when the caller was talking. Both issues went away when we used MiLi on handset mode, and of course, both batteries can be used without any issues whatsoever by just connecting the iPhones’ included Stereo Headset.
There were otherwise no surprises in the batteries’ performance. Both offer the same battery capacity, which is greater than Incase’s 1330mAh Power Slider and equivalent to the original Mophie Juice Pack for iPhone, but considerably lower than the 3300mAh TruePower iV. We tested each of the new batteries and found that, as expected, they fully recharged an empty iPhone 3G and had power left over afterwards, but not enough for anything close to a second full recharge. TruePower iV is physically bigger, but for $100, it offers a lot more capacity than either of these options, as well as more versatility due to its integrated camera lamp and a detachable front panel that allows it to resize for different iPhone models.
From our perspective, the iPhone 3G version of Juice Pack is unquestionably an improvement on its predecessor, with superior build quality—the rubber’s much better this time around—and a sleeker design at the same somewhat too high $100 price level.