Table A1.

Synthesis of main variables collected from RCTs (n = 9).

Study	Study Design	Duration	Participant Characteristic	Setting	Intervention	Dependent Variables	Outcome Measure	Comparison Group
[36]	RCT	Intervention exposure: 4 weeks	N = 26 Age 18~25 years Male (7) and Female (19) USA	Home	The SmPh app allows step tacking	App impact on cardiorespiratory fitness of college-going adults	Outcome: (i) Aerobic capacity; (ii) Ventilatory equivalent of carbondioxide (iii) Anaerobic threshold (iv) Treadmill distance and time; (v)Heart rate	Traditional walking prescription
[40]	RCT	Intervention exposure: 8 weeks	N = 95 Age >45 years Male (26) and Female (69) USA	Home	Three mobile apps shape the user towards more physical activity and fewer daily sedentary time	App impact on daily activity and sedentary time	Outcome: (i) Physical activity (i.e., accelerometer-derived moderate-to-vigorous physical activity) and (ii) Sedentary behavior (i.e., accelerometer-derived sedentary time, EMA-derived sitting time)	A diet-tracking control app
[35]	2-group RCT	Intervention exposure: 3 week, 20 week follow-up	N = 204 Age 21~60 years Male (48) and Female (156) USA	Home	(i) Behavior treatment; (ii) Handheld tool to record and self-regulate their targeted behaviors	The effect of Remote coaching supported by mobile tech- nology and financial incentives to improve diet and activity.	Outcome: (i) Fat and fruit/vegetable consumption; (ii) the saturated fat goal: the Harris–Benedict equation; (iii) Minutes of physical and sedentary activity	No control group
[33]	2-group RCT	Intervention exposure: 3-week intervention and a 3 months follow-up	N = 76 Age 18~40 years Female (65), Male (11) UK	Community, workplace home	(i) Fitbit One to measure steps and provides motivational messages; (ii) Internet-based motivational intervention	The effect of an Internet-based motivational intervention supported by pedometers on physical activity	Outcome: (i) Physical activity; (ii) Stages of Change Questionnaire for exercise; (iii) Decision Balance Questionnaire for exercise; (iv) Self-Efficacy Questionnaire; (v) Processes of Change Questionnaire	Without Fitbit one and internet-based motivational intervention
[34]	2-group RCT	Intervention exposure: 50-day, 20 week follow-up	N = 76 Age 18~65 years Female (82), Male (26) Australia	Home	(i) Active Team app to encourage friendly rivalry within friendship group; (ii)A pedometer to measure steps	The effect of an online social networking physical activity intervention with pedometers delivered via Facebook app	Outcome: Physical activities (Active Australia Survey, Assessment of Quality of Life-6D (AQoL-6D) scale, 36-item Short Form Health Survey)	Teams allocated to the control condition were placed on a waiting list to receive access to the intervention (app and pedometer)
[37]	2-group RCT	Intervention exposure:12 weeks	N = 30 Age 30~36 years pregnant women between 10 and 20 weeks of gestation USA	Home	(i) Initial Brief In-Person Session; (ii) Mobile phone app plus Fitbit	The effect of mobile health intervention in promoting physical activity in Pregnant women	Outcome: Physical activities (The Stanford Brief Physical Activity Survey) Other measures: (i) The Self-Efficacy for Physical Activity; (ii) survey, quiz, scale and checklist	Fitbit Ultra only (accelerometer)
[38]	3-group RCT	Intervention exposure:3 months	N = 210 Age 40~60 years Female (210) USA	Home	Use the app and accelerometer for 9 months	The effects of APP on levels of physical activity	Outcome: Physical activity Other measures: (i) Survey, quiz, scale	Control group: use accelerometer for 9 months
[21]	2-group RCT	Intervention exposure: 8 weeks	N = 128 Age 19–26 years Female (112), Male (16) Turkey	Home	(i) ERVE smartphone app; (ii) An educational video each week under the exercise education component of the ap; (iii) Researchers sent a message once a week to increase motivation.	The effects of a smartphone app on physical activity, quality of life, self-efficacy, and exercise motivation for inactive people	Primary outcome: self-efficacy, health-related quality of life, and motivational orientation for exercise Secondary outcome: BMI and levels of physical activity	No intervention
[41]	2-group RCT	Intervention exposure: 3 months	N = 650 Age 20–65 years Female (445) Male (205) Spain	Primary care center	(i) 5 min of lifestyle counseling before randomization; (ii) low-intensity intervention consisting of a smartphone with the EVIDENT 3 app and a smart band for 3 months;	The effects of a smartphone app combined with a smart band on weight loss, physical activity, and caloric intake in a population with overweight and obesity	(i) Body weight; (ii) Physical activity: International Physical Activity Questionnaire–Short Form; (iii) Caloric intake (kcal/day) and dietary habits: semiquantitative Food Frequency Questionnaire.	A brief counseling only