An analysis and evaluation of quality and behavioral change techniques among physical activity apps in China

Physical activity (PA) smartphone applications (apps) featuring at least one behavioral change technique (BCT) are ubiquitous. Although BCTs in PA apps and their quality have been evaluated in Western countries, such research in China is new. This study (1) characterizes the extent that BCTs are implemented in Chinese PA apps and (2) evaluates their features and quality.

Of 5,253 PA apps identified in five Android app stores in China, 51 top-ranked PA apps with more than 2 million total downloads and user rating above 4 (out of 5) were selected and assessed; their BCTs were scored using the BCT taxonomy(V1), and app quality was evaluated with the Mobile App Rating Scale (MARS). Correlations among the number of BCTs, app quality, app features, app downloads, and user ratings were examined.

Of the top-ranked apps, 62.7% allow behavioral tracking (i.e., pedometer), 9.8% promote Chinese dancing, and 17.6% offer monetary incentives. The average number of BCT categories included in the apps analyzed was 11 (SD = 3.51; range = 3-16), with the most common ones comprising feedback and monitoring (88.2%), goals and planning (82.4%), social support (81.4%), and reward and threat (80.4%). The average scores for objective and subjective quality of these apps were 3.90 (SD = 0.44) and 2.27 (SD = 0.61), respectively, as assessed by MARS. Moderate positive correlations were observed among the number of BCT incorporated, apps quality, app features, and their total downloads.

Chinese PA apps vary in the number of BCTs incorporated, with goals setting, feedback, social support, and reward being typical. App objective quality is moderate, with relatively low subjective quality. Generally, higher quality PA apps in China include more BCTs with more app features and downloads. These findings can guide the development of PA apps to mitigate physical inactivity in China-and elsewhere.