Hi, I'm working on an iPhone application that should work in offline and online modes.
In it's online mode it's supposed to feed all the information the user enters to a webservice backed by GWT/GAE. In it's offline mode it's supposed to store the information locally, and when connection is available sync it up to the web service.

Currently my plan is as follows:

1. Provide a connection between an app and a webservice using Protobuffers for efficient over-the-wire communication
2. Work with local DB using Core Data
3. Poll the network status, and when available sync the database and keep some sort of local-db-to-remote-db key synchronization.

The question is - am I in the right direction? Are the standard patterns for implementing this? Maybe someone can point me to an open-source application that works in a similar fashion?

I am really new to iPhone coding, and would be very glad to hear any suggestions.

Thanks