title: Health Behavior Theory in Popular Calorie Counting Apps: A Content Analysis.
abstract: BACKGROUND
  Although the Health & Fitness category of the Apple App Store features hundreds of calorie counting apps, the extent to which popular calorie counting apps include health behavior theory is unknown.
  
  
  OBJECTIVE
  This study evaluates the presence of health behavior theory in calorie counting apps.
  
  
  METHODS
  Data for this study came from an extensive content analysis of the 10 most popular calorie counting apps in the Health & Fitness category of the Apple App Store.
  
  
  RESULTS
  Each app was given a theory score to reflect the extent to which health behavior theory was integrated into the app. The highest possible score was 60. Out of the 10 apps evaluated, My Diet Coach obtained the highest theory score of 15. MapMyFitness and Yumget received the lowest scores of 0. The average theory score among the apps was 5.6.
  
  
  CONCLUSIONS
  Most of the calorie counting apps in the sample contained minimal health behavior theory.
authors.affiliation: Department of Health Science, Brigham Young University, Provo, UT, United States.
authors.forename: Siena F
authors.identifier: http://orcid.org/0000-0003-4601-0469
authors.initials: SF
authors.lastname: Davis
authors.forename: Marisa A
authors.identifier: http://orcid.org/0000-0002-5737-2812
authors.initials: MA
authors.lastname: Ellsworth
authors.forename: Hannah E
authors.identifier: http://orcid.org/0000-0003-4109-1634
authors.initials: HE
authors.lastname: Payne
authors.forename: Shelby M
authors.identifier: http://orcid.org/0000-0002-3546-7714
authors.initials: SM
authors.lastname: Hall
authors.forename: Joshua H
authors.identifier: http://orcid.org/0000-0003-1086-3865
authors.initials: JH
authors.lastname: West
authors.forename: Amber L
authors.identifier: http://orcid.org/0000-0002-6130-7925
authors.initials: AL
authors.lastname: Nordhagen
keywords: caloric restriction; cell phones; mobile applications; telemedicine; weight loss