{'fraction_non_alphanumeric': 0.045992115637319315, 'fraction_numerical': 0.02102496714848883, 'mean_word_length': 4.644444444444445, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 1, 'lorem ipsum': 0, 'www.': 1, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Busuu: how do users rate this app for language learning?

Busuu (https://www.busuu.com) is one of several existing Social Networking Sites for Language Learning (SNSLLs). According to Álvarez (2016), it has all the features an SNSLL should have. However, once Busuu migrated to a mobile compatible platform in 2016, it lost some of the social aspects of a Social Networking Site (SNS) determined by Boyd and Ellison (2008) and Duffy (2011). As the most used language learning platform worldwide (Busuu, n.d), the user experience of its learners is of interest to the field of ComputerAssisted Language Learning (CALL). A pilot study to see how users rate it was conducted at an English university for four weeks. This chapter shows the results of that research.