Table 1.

Summary of intervention effects on physical activity outcomes.

Study		Physical activity (PA) outcomes			Engagement
		Daily steps	Light, moderate, moderate-to-vigorous physical activity (MVPA), and vigorous PA	Sedentary behavior
App-alone studies
	Arrogi et al, 2017 [40]	—a	—	[++]b	—
	Bond et al, 2014 [48]	—	[+]c	[+]	—
	Choi et al, 2016 [38]	[-]d	—	—	xe
	Cowdery et al, 2015 [39]	—	[-]	—	—
	Fanning et al, 2017 [41]	—	[+]	—	x
	Glynn et al, 2014 [36]	[++]	—	—	—
	Korinek et al, 2018 [50]	[+]	—	—	—
	Pellegrini et al, 2015 [49]	—	[+/−]f	[-]	✓g
	Simons et al, 2018 [42]	—	[-]	—	x
	Walsh et al, 2016 [37]	[++]	—	—	—
App Web-based social networking studies
	Al Ayubi et al, 2014 [43]	[+]	—	—	✓
	Foster et al, 2010 [44]	[+]	—	—	✓
	Hurkmanns et al, 2018 [47]	—	[-]	—	—
	Pope et al, 2018 [46]	[+]	[+]	[+]	✓
	Torquati, Kolbe-Alexander et al, 2018 [45]	[-]	[-]	[-]	x

^aNot applicable.

^bSignificant between-group improvement in outcome.

^cSignificant within-group improvement in outcome.

^dNo improvement in outcome.

^eUnfavorable (low) engagement.

^fMixed results; engagement.

^gFavorable (high) engagement.