As someone who rides a bicycle in New York City, I am still waiting for the smartphone revolution.

There are dozens of public-transit apps for smartphones, offering all kinds of novel services. The offerings for the city’s bikers, by contrast, are pretty sparse.

First, an exception. For the kind of biker who cares how fast he climbs hills, a free app called Strava offers functionality akin to a dedicated GPS device. The app records the time, distance and average speed of a ride, and then allows riders to save their times in their profiles.

The neatest part, though, is comparing yourself with other riders who have done the same ride. This can be humbling. I’m proud to say that I can hit 30 miles an hour on the downhills in Central Park. But a rider named Rod Millott’s average speed for the entire loop around the park is nearly that fast, and he has done the six-mile route in 12 minutes 33 seconds. Sheesh. Be warned, there are a lot of people like Mr. Millott using this app. For some more reasonable competition, you can also follow your friends.

If you want a full biking GPS device, Strava will not replace it. On the other hand, Strava is free. (You can subscribe to the app’s advanced analytics for $5.99 a month or $59.99 a year.)