"Fallout Shelter" became the most popular free iOS application in the U.S. and UK within a day of its release, and the most popular iOS game on June 26, 2015. By June 12, 2016, Fallout Shelter had over 50 million players. Studio director Todd Howard estimated they had 75 million players by February 2017. By June 2019 the game was downloaded more than 150 million times. By June 2020 the game was downloaded more than 170 million times. Because of "Fallout Shelter"s success, the studio has been working on a second mobile title.