Object-C with PHP MYSQL

1) NSURLConnection and its delegate methods - you can send asynchronous request to your webserver to get this file and get notified when the data has been downloaded so the user interface is never blocked in your app.

Here's the documentation with some good examples from Apple:http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSURLConnection_Class/Reference/Reference.html

At the end of the download, you will have an NSData object which can then be converted back to a string using NSString *jsonContents = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding.

You can then use a JSON parser library - I recommend SBJSON https://github.com/stig/json-framework- which will parse the data and return it as a dictionary or array depending on your structure.

From there you can access your tables and value with valueForKey in dictionaries orobjectAtIndex: in arrays and then map it into your chosen local storage, for which I recommend Coredata (or you could use sqlite if you are familiar with it too).