My iPhone says the DJI Fly app is taking up almost 4gb of storage.
I've deleted all media from the app via the "Gallery" menu.




And also cleared the cache from within the app.



But apparently the app files are still taking up over 3gb of storage space.



Is there something I'm missing here? I've looked through the file list from the above screen and there's nothing particularly big there.

It seems there is a bug in IOS 15 with the storage not being displayed / updated properly.  I was clearing down storage on my iPhone 12 Pro Max getting ready to upgrade and had this with several large apps.