“…Conversational agents were delivered through a variety of means in the included studies. Most (n=23) were smartphone apps [ 30 , 46 - 50 , 53 , 55 , 58 - 61 , 64 , 67 , 70 , 71 , 75 , 77 , 81 , 83 , 85 , 86 , 88 ]; web based (n=5) [ 57 , 66 , 73 , 74 , 82 ]; desktop computer based (n=2) [ 65 , 79 ]; used smartphone-embedded software (n=6; eg, Siri, Google Assistant, Alexa, etc) [ 44 , 51 , 62 , 76 , 84 , 87 ], Telegram [ 45 , 78 ], WeChat [ 72 ], SMS and multimedia messaging service [ 89 ], Windows live messenger [ 56 ], or Facebook Messenger [ 52 , 80 ]; and 4 were made available on more than 1 platform [ 53 , 59 , 68 , 83 ]. Three studies did not specify the method of conversational agent delivery [ 54 , 63 , 69 ].…”