Money a motivator in exercise app

Created by a pair of Harvard students, it purports to help 92% of users live a healthier life by using money as a motivator.

Pact requires users to set the number of exercise sessions they will complete in the coming week. They then agree to a fine ($5–50) for every session they miss. Those who meet their goals are rewarded by receiving money paid by those who fail (25–60 cents per workout).

In order to verify that the exercise is being