App stores allow developers to publish new updates directly to users. Users evaluate and leave public reviews of their opinions and experiences for others to see. App ratings and reviews are a purchase determinant for users, and are free user-based usability tests. Existing literature offers approaches to extract information from or to summarise app reviews, but what can we say about the authors themselves? We analysed about 8.7 million iOS app reviews written by over 5.5 million unique authors. We found that 71.5% of authors only wrote one review. Only 13,224 instances of authors re-reviewing were observed, by 12,667 authors for 3,345 apps.