Before the iPhone came out, I ran with a watch that uses GPS satellite technology to keep tabs on my pace, distance and other measurements when I run. Like a lot of runners, I’ve gotten hooked on the ability to tally up how many miles I put in on the road and to use my watch to motivate myself to run a bit farther or faster. The Adidas miCoach These days ordinary smartphones have GPS built into them and developers are creating apps that use the technology for tracking runs. Plus some of the apps do a lot more than a GPS watch: They can help you devise a training schedule prior to races and more actively coach you during your runs. I spent a couple of weeks using three running apps for the iPhone—Running Method’s Run Coach Pro, FitnessKeeper’s RunKeeper Pro and Adidas’ miCoach—with the goal of seeing whether any of them could be an adequate substitute for my GPS watch, a Garmin (GRMN) Forerunner 305, which cost me $190 two years ago with a companion heart-rate monitor (the same package now sells for $153 on Amazon). (There’s a BlackBerry version of miCoach app and an Android app is in the works.) The answer, in one case, is an emphatic yes. There are, however, some tradeoffs to running with an iPhone that might make using any running app a deal-killer for some people. First, the iPhone is a handsome device that faces a risk of disfigurement from your sweaty hands as well as from falling onto concrete so runners will want to consider buying an accessory that keeps the phone safe. My Garmin is a giant of a watch, but at least it doesn’t require its own carrying case on a run, unlike the iPhone. Armbands for the iPhone let Read More