Re: why is my storage running out?
Storage or RAM? Storage is not affected by opening an app unless its the first time your opening the app and it's building cache for the app or it starts to update once you open it. If you have very little free space of storage, you may get a message saying so when opening apps tho as a warning/reminder.
Now opening a new app will take more away from your available RAM. Android does a good job on managing RAM. If it comes down to needing more, it will simply hibernate or kill non priority background processes.
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