“…Physical activity has attracted the most research interest, making up 38% of all the reviewed studies, followed by healthy eating with a total of 25%. [57], [64], [72], [89] 13 Goal Setting Theory [15], [23], [75], [77], [79] 5 Social Conformity Theory [35], [57], [ [36], [37], [39]- [43], [45]- [53], [55], [56], [58]- [63], [65]- [68], [70], [71], [73], [74], [76], [81]- [88] [50], [52], [54], [56], [59], [61], [62], [66] [73]- [75], [79] [15], [85], [86], [88] 38% Tracking and monitoring (19) Social support, sharing, and comparison (17) Competition, leaderboard, ranking (10) Reward, points, credits (10) Goal and Objectives (9) Audio, Visual and Textual Feedback (8) Transtheoretical Model (4) Goal Setting Theory ...…”