Hi,
You can use SignalR to accomplish your work.
What is SignalR ?
Quote:
ASP.NET SignalR is a new library for ASP.NET developers that makes it incredibly simple to add real-time web functionality to your applications. What is "real-time web" functionality? It's the ability to have your server-side code push content to the connected clients as it happens, in real-time.
You may have heard of WebSockets, a new HTML5 API that enables bi-directional communication between the browser and server. SignalR will use WebSockets under the covers when it's available, and gracefully fallback to other techniques and technologies when it isn't, while your application code stays the same.
SignalR client for Objective C :
https://github.com/DyKnow/SignalR-ObjC[
^]
You could send a notification to your client about a new file arrived and then that client application will download file from your desire location. This way you will be able to push file to client from Server.
Thanks,
Suvabrata