Virulent flaming notwithstanding, I continue to believe the "smartphone bike computer" category has legs. To that end, here’s a look at Wahoo Fitness’ Fisica, an iPhone case/bike mount that gives iPhone owners full power and GPS functionality for $120.

Hardware

Like the iBike Dash, the Fisica is a weatherproof case for the iPhone 3G, 3GS, and 4, with an ANT+ transceiver built in (check the videos here for a full rundown on the Fisica.) Unlike the Dash, the Fisica doesn’t house a supplemental battery, which lends it a much lower profile and better aesthetics. It’s still much bigger than a typical bike computer, but it’s creeping towards the ‘tolerable’ range. A piggyback battery is available (which I didn’t test), but my iPhone 4 handled 4 hour rides with more than 20% battery to spare. 3G/3GS owners will probably have issues with battery life for longer rides. (Wahoo claims 9+ hours w/o GPS, 5+ w/ GPS for the iPhone 4.)

The case is a sturdy two piece design, with six snaps and a rubber liner to keep out moisture. Mounting and removing the phone’s a bit more painstaking than with the Dash, so on muffin stops I just took the whole case with me rather than removing the phone.

I had a bit of trouble with the stem mount. My pre-production sample came with thinner zip ties, one of which snapped when I hit a big bump. Switching to heavier zip ties fixed this problem, and the Fisica will ship with heavier zip ties. Of course, this just serves to highlight the unavoidable bugaboo of the iPhone bike computer concept: it’s BIG.

Software

The most intriguing aspect of the Fisica is that Wahoo has opened up its API to third party programmers. Wahoo has an app available for free, but the real interesting thing will be to see what others create in the future. One promising app listed in Wahoo’s directory is EZ-Bike, which, among other things, streams your bike data to a desktop computer so you can train with your stats overlaid onto your videos, like a Tacx VR or an ErgVideo for a fraction of the price.

Wahoo’s own app is simple and clean. Pairing up your sensors is quick and intuitive, and the app stores multiple sensors so you can switch between bikes. The power display is especially nice, as it simultaneously displays power, average power, normalized power, intensity factor, TSS, and mean max power for 20s, 1m, 5m, 20m, and 1h. Raising each of those numbers is a real boredom killer on the trainer. Once you’re done with the workout you simply email the file to yourself or upload to cyclingpeaks.

Verdict

So why would you want one of these? Here’s some possible reasons:

•You have an iPhone, you need an ANT+ computer head, and this is the cheapest option available.

•You want GPS and power for $120 instead of $450 for the Garmin 800.

•You’re an Apple fanboy and you want to do everything with your iPhone.

•You train at night and you need an illuminated display.

•You want something you can use on MTB rides to get speed and altitude from GPS data, without adding sensors to your bike.

•You need more stimulation on indoor sessions.

•You’re a triathlete and you want something that’ll record bike and stride sensor data.

•You’re a data freak and you want to see where in the race you attacked (or blew up spectacularly), and you figure your phone’s safer on your bars than in a bag by the registration table.

So there you have it, an ANT+ bike computer that does a ton of stuff, has unlimited potential on the software side, and is the cheapest option out there if you’re an iPhone owner. And to pre-empt the inevitable comment, here’s a shot of a porn streaming trainer ride.