I've written many iPhone Applications that have pulled data from web services and I've worked on synchronizing data between an iPhone App and a Web Application, but I've always felt that there is probably a better way to handle the synchronization.

I'd like to know what strategies you have used to synchronize data between your iPhone(read: mobile) Apps and your Rails(read: web) Applications.

• Are there any strategies that scale particularly well?
• How have you dealt with large amounts of data? (Do you use paged responses?)
• How do you make sure that data is not overwritten?
• Is there a reason to avoid Ruby on Rails?
  • if so, can you suggest an alternative? What is better about the alternative?
• What strategies have failed?
  • Why do you believe that those strategies failed?

I would like to be able to keep all of the data modifications on the server, but the particular application I am about to start work on will need the ability to operate while disconnected from the network.

The user will be able to update data on the mobile device and update data through the web application.

When the user's mobile device connects to the server any local changes will be pushed to the server.