You need motivational support to turn knowledge into action

Behavior Change Techniques in Top-Ranked Mobile Apps for Physical Activity
American Journal of Preventive Medicine, 46(6): 649–652, June 2014
David E. Conroy, PhD, et al.
http://www.ajpmonline.org/article/S0749-3797(14)00040-3/abstract

Methods:
Top-ranked apps (n=167) were identified on August 28, 2013, and coded using the Coventry, Aberdeen and London–Revised (CALO-RE) taxonomy of behavior change techniques during the following month.

Conclusions:
Behavior change techniques are not widely marketed in contemporary physical activity apps.
Based on the available descriptions and functions of the observed techniques in contemporary health behavior theories, people may need multiple apps to initiate and maintain behavior change.

journalistic version:
Most Fitness Apps Don’t Use Proven Motivational Techniques
May 06, 2014
http://www.npr.org/blogs/health/2014/05/06/310136269/most-fitness-apps-dont-use-proven-motivational-techniques
“You need motivational support to turn that knowledge into action,” says David Conroy, a kinesiology professor at Penn State who led the study

related:

4 Proven Ways to Increase Your Motivation to Exercise
July 2016
http://time.com/4410412/increase-motivation-exercise

https://franzcalvo.wordpress.com/2015/10/05/personal-life-contracts

http://www.npr.org/blogs/health/2013/01/16/169524178/skin-doctors-question-accuracy-of-apps-for-cancer-risk