InFallout Shelter, you take control of your very own iconic Vault from Vault-Tec, where you’ll be responsible forkeeping your Dwellers happyand protecting them from dangers from the outside world, called the Wasteland. You will undoubtedly put a ton of time and effort into designing the layout of your Vault, gaining new Vault Dwellers, and ensuring they have enough resources to survive.
It is only natural, then, that you are wondering ifFallout Shelterruns when your device is closed and if you need to worry about anything happening to your Vault while you are away for short or long periods. Here is the answer to that question — and much more.

Does Fallout Shelter Pause When You Exit?
Yes,Fallout Shelterdoes run when closed — kind of. What the game really does is calculate the time you were away and then catch up on specific aspects of the game when you relaunch it and open your Vault, making it seem like it is running in the background.
During the game’s offline calculation, you’ll observe progress in your Vault in various ways. Your Vault Dwellers will continueexploring the wastelandwhile encountering events, crafting items, ortraining a SPECIAL. As your Vault continues to ‘run’ in your absence, it’s essential tomaintain a stockpile of resources. This proactive approach will prevent you from returning to unpleasant surprises and ensure the stability of your Vault.

Ensuring your vault has enough resourcesis super important because your resources will continue to drop for four minutes during the offline calculation, and the production of your rooms stops after four minutes. To get around this, you can have aMr. HandyorSnip Snipcollect resources in your rooms while you are away. Whenyour Snip Snipgathers your resources while you are offline, it is a great way to complete tasks like ‘collect x amount in a minute’ since the timer stops, but the generated product is still collected.
Luckily, random incidents and vault attacks no longer happen when the game is closed like it used to. Nothing was worse than logging into the game to find molerats, a fire, or ghouls that had killed all your Vault inhabitants. Still, specific circumstances could still happen, especially for those who play on mobile devices.

For mobile and tablet players, make sure you go to your device’s home screen orforce the app to close. When you do so, the game will adhere to the four-minute rule before pausing resource drop and production gains. However, if you close your tablet cover or leave the app running in the background, there is a chance it could continue playing as if you were there, which would be disastrous. When this happens, your vault dwellers could die, especially if your resources are in the red or your vault dwellers are already close to death since they can and will die when you are away.
However, regardless of the platform you play on, you shouldalways use the Save and Exit buttonin the Settings menu when exitingFallout Shelter, whenever possible. This will close out your Vault and ensure there are no unexpected issues with how the game handles being offline.