iPump Total Body: iPump has developed some 20 fitness apps that the iTunes store sells, but Total Body ($2.99) is perhaps the least specialized of these, and thus the best to start with. iPump gives you speech, text, and image presentations of preset workouts, each one including some cardio for warm-up and warm-down. When you're done with a workout, the app notes the accomplishment and keeps track of which ones you've already completed. The idea is to cycle through all of the workouts so that you never get bored.

RunKeeper: RunKeeper ($9.99) is a Nike+ app that works with your iPhone. It tracks your runs using the , and then displays your jogging or walking pace, your distance, and your time. It can even spit out a nice bar graph displaying your speed over a given time period. After your run is over, you can log on to to see your run displayed on a Google map. What didn't RunKeeper's developers think of?

iSpinning: iSpinning is a great (and free) little app for road biking and mountain biking workouts. It uses a growing number of body sensors to track stuff like your heart rate (current, average, and max), biking time, calories burned, speed, distance, and power. You can customize the app's dashboard on your iPhone to display just the metrics you care about.

HangTimer: This $10 app lets snowboarders, skiers, and skateboarders measure their jumps. It identifies the exact length of time they were airborne and the exact GPS location where the jump took place. HangTimer also delivers snow reports, detects ski resorts, and maintains a list of your 10 best jumps.

Quitter: Smoking and fitness, of course, don't mix. The free Quitter app keeps track of the number of days you have not smoked a cigarette, along with the amount of money you've saved by removing cigarettes from your budget.