Personalized iOS app

Please help me find solutions for the following tasks.

  1. Is it possible to make server-sided applications in UE4?

  2. The application has hundreds of levels. Users should be able to download only a handful of those levels. Each user chooses a customized set of levels.

I have the same question, would love to get some input on this. Has anyone been able to build an app with more than just the UE view (i.e. native iOS tabs) and then load game levels dynamically from the server? I imagine it can be done with separate PAK files but I can’t get anything to work