I have seen people have made level editors for their C2 games using C2 so I would imagine it is possible to create a presentation-builder app. However don't underestimate the difficulty of doing such a thing, not because C2 is a difficult program to use but the concept is a complex one to execute. You would have to make one app for creating the presentation and exporting the data and make another app that loads and displays the presentation - the same basic concept of the Unity Web Player.
You will need to plan:
- How to store the user's entered values for headings, text, animations
- How to manage each slide, triggers, etc
- How to store images they have chosen
- How to package their data to be recalled later by the 'player'
- How to recall that data
And so on. This is all perfectly achievable with a lot of thought, planning and clever events management. IMO you would be better off using C2 to build your proof-of-concept prototype (one that is functional) and use it as the blueprint for building in another framework that is geared more towards apps. App frameworks have easier access to libraries you will need to enable cloud storage, payment options, user accounts, exporting etc all things to make it a 'killer' app, or at least one worth using. Good luck! I hope you share your progress on here.
[EDIT] I guess to integrate cloud storage and the other features I mentioned you could figure out how to build an app 'shell' in another framework that loads the editor you have created in C2 and your own C2 plugin for interacting with that shell.