What's the best cleanup app for my iPhone XS

The Photos app has a Duplicates feature which will find and help you eliminate them. The Mail app has a spam feature, ditto. And there is no "generally".

don't really think that is a thing, in ios the apps you get from app store are sandboxed so for security reasons they can't alter the data of the core system or the other apps in your ios device.

What's the best cleanup app......

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