There has been a growing number of reviews of mobile language learning (MLL) conducted on various aspects of this field of study over the last two decades. However, unlike in other fields, there is a paucity of overviews of reviews that assess and integrate findings from multiple reviews, and that compare and contrast such findings, or establish gaps in existing reviews. The current overview examined 17 review studies published between 2010 and 2018, and investigated twenty-three characteristics extracted from these reviews with a view to comparing them and synthesising the main findings of these reviews. The selection criteria used were: reviews published between 2010 and June 2018, reviews published in peer-reviewed journals, use of at least one bibliographic database, reviews focusing on mobile language learning (MLL) or having MLL as one of the learning domains, and reviews published in English. Some of the findings of this overview are: most reviews were qualitative in nature and few of them had clearly and precisely formulated purposes; there is a lack of theoretical frameworks by the majority of these review studies; there were 25 precise and specific mobile device typologies reported by eleven reviews, of which personal digital assistants (PDAs) and mobile phones were the two most reported mobile device types, respectively; language was the most reported subject area followed by mathematics; and fewer reviews mentioned and specified their research designs, their coding procedures, their inter-rater reliability agreement, and their quality assessment. Finally, English as a foreign language (EFL) was the major target language and vocabulary learning was the main focus of MLL.