Will All Desktop Features Be Added to Scrivener for iOS?
The short answer to this question is "no"! Scrivener for iOS has been designed from the ground up as an iOS app. We've tried to take the essence of Scrivener and bring it to mobile devices. All the core features are there: the ability to create an outline, to view the corkboard (on the iPad), to work on a manuscript piece-by-piece, to import and refer to research, and even to refer to more than one document at the same time (again, on the iPad). However, it's simply not possible to implement every macOS or Windows feature in the iOS version.
As powerful as iOS is, the devices on which it runs are not as powerful (and do not have as much memory) as desktop machines. Moreover, Apple has designed iOS to be streamlined and much simpler than macOS. Its interface is much "flatter" and has less depth. On macOS and Windows, there is a menu bar into which can be crammed any number of features, all tucked away and accessible only as you need them. There's also the toolbar, which can contain icons for common commands, and which the user can customise.
There is no equivalent of the menu or toolbar on iOS. On iOS, you can fit a limited number of icons along the top of the navigation bar and a few in the footer bar (fewer on the iPhone) and that's it. You can use popovers to provide menu-like controls (such as the formatting popover in Scrivener for iOS), but if you tried to turn those into fully-fledged macOS-like menus, a touch-based app would soon become unusable.
Some apps do manage to have feature-equivalence between iOS and macOS versions of course, but such apps are either much simpler or have achieved this by redesigning the macOS version to be as flat as the iOS version. To achieve anything similar we would have to eviscerate the macOS and Windows versions, removing hundreds of features - we couldn't do it by adding hundreds of features to the iOS version.
So, UI design and space are the two main reasons that feature equivalence is impossible. Other features (such as Scrivenings) could take up too much memory, especially for huge manuscripts with many images.
For these reasons, there are no current plans to bring features such as Scrivenings, collections, keywords, snapshots or custom meta-data (to name but a few) to the iOS version.
There are other features we would like to incorporate in the future, but which provide technical difficulties. For instance, there are no UI or memory limitations to providing ePub support, but it is still a huge technical challenge because of the limitations in rich text to HTML conversion currently available. (The desktop versions have thousands of lines of code to work around this which are not transferrable.) So, there are features such as this which are on the list, but might take a good while to make it to the iOS version. (A tip on Epub: you can export from Scrivener for iOS as .docx to Pages, and then create an ePub file in Pages for now.)
This is not to say we won't be updating the iOS version and adding new features---we will, and we have been doing so! But we've seen some reviews from users complaining that we haven't yet added this or that macOS feature, and so we would like to dispel any misconceptions about what is possible on iOS. We think Scrivener for iOS is a hugely powerful standalone writing app and we're immensely proud of it, but anyone expecting all of the features of Scrivener for macOS gradually making their way to iOS will unfortunately be disappointed. (Of course, there is a reason that the iOS version is less than half the price of the desktop versions!)