Unleashed by SYBO and Kiloo back in May 2012, Subway Surfers managed to break the 400 million downloads barrier last year, thus becoming the most downloaded game of 2017 worldwide. Earlier this month, it also reached the 1 billion downloads milestone, so now this title is the most downloaded game on Google Play.
https://www.notebookcheck.net/Subway-Surfers-becomes-the-first-game-to-hit-1-billion-downloads.289978.0.html