Your get-fit goals are all shiny and new at the beginning of the year, but by the time February rolls around you might need a kick in the pants to keep moving. These three apps should do the trick:
Zombies, Run! In this audio book-meets-video game app, you become the main character in a zombie apocalypse, collecting tools and supplies as you run. Sync your favorite workout playlist with the app, and listen to the story unfold between songs. The best part: You'll hear groaning when the brain-eaters are close, and if you don't speed up enough (your phone's GPS tracks your speed), it's game over. (Available for iPhone and Android, $8, zombiesrungame.com)
Charity Miles Select one of several well-known charities to sponsor (right now, beneficiaries include RED, Habitat for Humanity, and Feeding America, among others), and then start moving. Every mile logged earns 10 cents (biking) or 25 cents (running or walking) for the organization of your choice. After all, it's hard to complain about a workout when your pavement-pounding could help feed families or supply antiretroviral drugs to those in need. (Available for iPhone and Android, free, charitymiles.org)
Gym Pact Consider this a high-tech way to bribe yourself to get moving. Commit to a certain number of days per week at the gym, and decide how much you're willing to pay if you're too lazy to lace up. At the end of the week, users who skipped their sweat sessions feed the pool—and winnings are split among the more dedicated. (Available for iPhone and Android, free, gym-pact.com)
Need more tools to help tackle your New Year's resolution? Check out our 4-week plans for bulking up, getting lean, looking better, and feeling younger.