There's no doubt that exercise does a body good. But a new batch of smartphone apps allows you to do good simply by moving your body.
Charity Miles(free, iPhone and Android) awards 25 cents per mile to walkers and runners and 10 cents per mile to cyclists, which can be donated to a choice of nonprofits such as Habitat for Humanity and Autism Speaks.
Plus 3 (free, iPhone) similarly turns exercise into money for charity but offers more activity options including weight training and Zumba.
LifeKraze (free, iPhone) allows members to give one another points for racking up fitness goals as varied as walking to work and climbing Mount Everest. The points can be used to make donations.
Run4Good (free, iPhone), a GPS-enabled app by the apparel brand Saucony, calculates miles walked or run. When the total for all members hits that month's goal, the company doubles its donations to groups fighting childhood obesity.
Striiv is a "smart" pedometer ($99.95) with built-in apps for the iPhone that count every step toward a donation to charity.