“…Five articles [36,38,41,49,50] have researched the assimilation of Facebook in formal English learning whereas only one article [42] employed Facebook for informal English learning. About a third of the total articles reviewed [29,35,37,39,40,45,46,48,[51][52][53]57] have not specified any SNS platform in the research, indicating that a lot of studies were done to investigate the influence of SNS as a whole on learning rather than just a single platform. Instagram may be regarded as the second most popular medium for informal learning, with two articles [43,47] devoted to the topic, but just one article [58] focused on its application in formal learning.…”