When we reviewed the original Apple iPhone, we loved its snazzy Web browser, lovely interface, and top-notch media player. Its phone, however, didn't set us over the edge. Not only is the volume quiet, but also the reception wavers from time to time. Sure, it's perfectly good for making calls, but we were hoping for better from such a high-profile device. That's why we were excited when Griffin Technologies introduced its ClearBoost case. The ClearBoost is like no other iPhone accessory in that it promises to address two issues at once: protect the iPhone from scratches and nicks while giving the handset's antenna a boost. We were skeptical, too, so we had to give it a try.
After some testing, we can report that the ClearBoost accomplishes its first goal admirably. The case has a sturdy build and it comes with a few accessories to protect your device. Its success at reaching the second goal, however, isn't consistent. Though the actual "boost" can be enough to improve your signal measurably under some circumstances, it doesn't appear to help when you really need it. But even so, it's not a bad buy at $34.99, particularly if you need a new iPhone case and you get mediocre reception in your home or office. You should get some difference, but don't expect it to suddenly deliver a crystal clear signal. Also, keep in mind that the ClearBoost is not designed to fit the new iPhone 3G.
We give the ClearBoost points for its simple and minimalist design. The black plastic shell wraps around the back and edges of the iPhone, while leaving holes for the camera lens, the exterior controls and ports, and the SIM card slot. The case snaps on very securely with a loud click. In fact, the fit was so solid that the ClearBoost was a bit difficult to remove. Naturally, the case will make your iPhone a little thicker, but we got used to the extra girth quickly. On the downside, you can't use your iPhone dock when the case is on.
We liked that the case came with two accessories. Since the ClearBoost leaves your display exposed, it comes with a plastic skin to protect the screen from any scrapes. The skin affixes easily and leaves gaps for the Home button and the earpiece. You also get a cleaning cloth, which is especially useful if you've lost the cloth that came with your iPhone (as we have).
The ClearBoost's boosting capability comes from a stubby antenna that extends from the top of the case. It's only half an inch tall and is covered in a rubbery material that extends partway down the back of the phone. Inside the antenna is a copper wire for catching the signal. The wire extends down the interior of the case to a large coil at its bottom end. The coil is designed to make contact with the iPhone's internal antenna.
The ClearBoost works best in places where you have two or three bars of reception. In those instances, we noticed we got an extra bar (and rarely an extra two) after we snapped on the case. The change wasn't noticeable immediately, but we did get the extra boost after a few seconds. A better test however, is to use your iPhone's "field test mode." To get there, type "3001#12345#" into the your iPhone's keypad and press the Call button. In the top right corner of the screen you'll notice a dBm number (basically, decibels per milliwatt) that represents the signal strength that your phone is receiving. The lower the number, the better the signal.
During testing of the ClearBoost, our dBm number dropped much of the time, particularly in the aforementioned places where we had some reception to start. The effect wasn't always detectable, but the number did indeed change. When the clarity improved audibly we noticed less static and fewer cut-outs, but our callers' voice quality sounded about the same.
When we had just one bar, however, the ClearBoost made no noticeable difference. The bars and dBm did not change significantly, and we didn't notice any audible improvement in our calls. We tried the ClearBoost in a few places with poor reception and had the same result each time. That is really too bad, since those are the moments when you'd need the ClearBoost most. Conversely, on places with great reception the ClearBoost didn't make a difference either. But that doesn't upset us since the quality in those areas was good enough in the first place.