Yes, this is something I have planned for version 1.1. The tricky part is the workflow for this “export feature”.
There are two obvious places to put the UI:
1) In the Share Sheet
2) In the Edit UI
In the Share Sheet, there is already a save to Files, but as you point out, that will save a JPEG. I could add some extra choices, like Save TIFF to Files or something like that. It’s a little tricky because the original image may not be present, so the app would have to download the image and render (since you wouldn’t be in Edit at that point)
The Edit UI may be a better place for this – there could be an Export button or something that allowed you to export the image right from there. You could choose to save it normally into the library or not.
Or perhaps, it could be connected to the Done button -> by default it would save to the library, or perhaps a preference would prompt you, giving you choices of what to do, including “save to the library” or “save JPEG to Files” or “save TIFF to Files”. Or maybe even save as a new image in the library.
I’d like to avoid doing all of them, and I don’t want to make the UI very clunky. I’m interested in your (and other customers’) thoughts on this. Space in the UI is pretty limited right now, especially on a small screen iPhone.