I can't believe there's no app for that!

September 29, 2009 9:48 AM

Could I possibly use my iPhone as a bike computer?

Yes, there are some biking-related apps for the iPhone, but they all seem to rely on GPS. Mine is a 1st gen iPhone, so I can't use those. But even when I eventually upgrade to a 3G S, it just seems slow, inaccurate and wasteful (not to mention silly) to rely on satellites in outer space in order to track the speed and distance travelled on my bicycle.
A Google search reveals that some genius in Japan created a hack for this last year, but alas, it hasn't evolved into a consumer product to the best of my knowledge.
I'm sure there's a simpler way to achieve this using Apple's Nike + iPod doohickey. It's a physical accessory that wirelessly counts clicks from your running shoe. Couldn't it be modified to count blips from a wheel-mounted magnet? Has anyone tried it?
Or will I have to... gasp! ...buy an actual bike computer and use two devices where one might have sufficed?
Thanks in advance for any further info.

posted by Silky Slim to computers & internet (13 comments total)

Here's a teardwon of the Nike doohickey. Happy hacking
posted by Confess, Fletch at 9:57 AM on September 29

it just seems slow, inaccurate and wasteful (not to mention silly) to rely on satellites in outer space in order to track the speed and distance travelled on my bicycle.

I don't know if you've tried the Apple Maps application, but it seems even more inaccurate and slow to rely on cel tower triangulation for position. I don't know if it could be used to measure speed.

You might find this helpful, if you just want to measure speed.
posted by Blazecock Pileon at 10:00 AM on September 29

The Nike+ doesn't just count footfalls - it actually senses, using accellerometers, effective stride length. I base this on using two widely different stride lengths for different laps around a park and still getting the same distance.
posted by notsnot at 10:00 AM on September 29

There are some iPhone apps that serve as bike computers. Using GPS (which most do) offers the benefit of actually tracking your route, which makes all kinds of interesting things possible.

The problem with using the iPhone as a bike computer is 1) you need to keep that app running, which means that you run down the battery and can't use any other features (unless they've been incorporated into the app, which some developers have done). You can overcome the battery issue to some extent by dimming the screen, shutting off bluetooth and wifi, typical power-management stuff. Or you could get a piggbyack battery.

I believe there's one app that relies on a custom rotation-counter, iRPM, but it actually communicates with the counter over wifi (!), and details are pretty thin.

Apple only opened the accessory port up to developers with OS 3.0. I've been expecting someone to develop a bike-computer mount that would take advantage of this, but so far, I'm not aware of one.
posted by adamrice at 10:23 AM on September 29

it's just not that practical. a decent bike computer relies on mechanical movement (cadence sensor magnets) and efficient battery usage. an even better bike computer relies on GPS for positioning. the iphone 1g has neither. you're better off just spending $20 on a cheap cateye, $20 on a black & white garmin GPS for your back pocket, and using sporttracks to combine the two data sets. Or get a garmin 705 :)
posted by Señor Pantalones at 10:36 AM on September 29 [1 favorite has favorites]

But even when I eventually upgrade to a 3G S, it just seems slow, inaccurate and wasteful (not to mention silly) to rely on satellites in outer space in order to track the speed and distance travelled on my bicycle.

It seems silly and wasteful to rely on a fragile and expensive iPhone with a known short and limited battery life to replace a $20 bike computer that will last years on one battery. Even the Nike iPod sport kit costs more than a bike computer. Also consider that to view the iPhone continuously, the screen will need to be on, which will probably reduce the battery life considerably, and the connection with the transmitter device will also use the battery.
posted by meowzilla at 10:41 AM on September 29

I don't know if it's practical, but i think it would be wild if someone made a mount for the iphone on a bike that was able to use the cycling to generate electricity to supplement the battery of the iphone.

If anyone uses that idea, put my name in the patent. Just say thanks.
posted by bDiddy at 10:45 AM on September 29

This is how you make the charger for the bike. It is very practical.
posted by bravowhiskey at 11:44 AM on September 29

Go to Page 2 in this Slate article, there's a section on iPhone bike apps.
posted by exhilaration at 12:04 PM on September 29

$20 bike computer FTW.
posted by craven_morhead at 12:20 PM on September 29

I don't see what's so "wasteful" l with using the iPhone as a bike computer. You get the exact same data and GPS is going to be more accurate than a bike computer for distance measurements, plus you can plot your location and route. You're going to carry your phone anyways, you might as well use it.

I use everytrail on my Android phone, and it works well. There is also an iPhone version as well as an REI branded iPhone app that is built by everytrail has some extra info.
posted by wongcorgi at 12:52 PM on September 29

Don't wait for the iPhone app or the Nike/iPod jerry-rig. Get a bike computer. Nobody is going to steal a $20 Cateye bike computer off your bike.
posted by birdwatcher at 2:53 PM on September 29

I guess the $20 bike computer is the best solution right now :^(
posted by Silky Slim at 6:18 AM on November 14