Files app introduced with iOS 11 is a file manager from Apple. Or to be correct, manager of sandboxes. Every app in iOS has its own storage and user has files stored within these sandboxes, app by app. You can’t have the same file in multiple storages, so if you need to work on one file in different apps, you have to copy and copy between sandboxes via “Open with…” feature. Big changes were made in iOS 8 with features called “Document Provider” and “Document Picker”, but sandbox system was still present. In iOS 11, Apple relased Files app. Within this app, you were able to watch all sandboxes in one place – of course, developers have to support this new file manager. Files app itself did not store any files – it was just manager of sandboxes. With upcoming iPadOS, things may change.
On WWDC 2019 keynote, where Apple introduced “iOS for iPad”, Craig Federighi, a showman with iconic hairstyle, presented new features coming to iPadOS. If you were looking carefully, you may be attracted by “Local Storage” showed on the big screen:
Will Files app finally support native local storage? Based on answers from people using iPadOS beta, yes. As Apple said, Files app is now compatible with external disks and SMB standard to connect to computers. Personally, if FTP(S) access is supported too, or if some FTP client for iOS will provide decent Files app integration, it may be end of classic file managers for iOS, like “Documents by Readdle” or “FE File Explorer Pro”, unless they provide extra features to compete with native solution from Apple.
I’m glad that Apple is finally taking care of iPads’ filesystem, you have even “Downloads” folder within the Files app to store files downloaded by new desktop-class Safari for iPads. That’s just amazing and I can’t wait for testing public beta, which will come out in July.