If your device is tight on storage, deleting rarely-used apps is one way to free up space. But the problem with that is that you lose your settings and data for the app.
A nice feature in iOS 11 will allow you to delete apps, but retain their settings and data. As spotted by Cydia Geeks, iOS 11 introduces a new storage-management option called Offload App.
Inside General > iPhone Storage, scroll down to the app you want to remove, tap on it and select Offload App. If you do want to remove data and settings, select Delete App instead. The settings screen shows you the space used by the app itself and by its documents and data.