Fallout Shelter Online

Fallout Shelter Online is a mobile game developed by Shengqu Games, published by Bethesda Softworks, and distributed by Gaea Mobile.

Story
The game takes place in the Commonwealth. The protagonist is the future successor to their vault's overseer. When the overseer left the vault unexpectedly with a device for distributing the resources of the vault, the player becomes the new leader and begins the search for the overseer and the device they took. After the main plot is completed, the protagonist travels to the Capital Wasteland to assist Harold and Hannibal Hamlin in fighting slavers and the Enclave.