It is EASY. If you control both parts of the system.
The magic word here is PLIST.
IBM has a great example of the original iPhone project and the deployment of the Google work engine.
http://www.ibm.com/developerworks/web/library/wa-aj-iphone/
Here is some ultra basic code.
NSMutableArray *myArray = [NSMutableArray arrayWithObjects:@"one",@"two",nil];
NSURL *url = [NSURL URLWithString:@"http://www.hurl.ws/api/"];
ok = [myArray writeToURL:url atomically:NO];
if(ok) NSLog(@"saved worked");
PLIST URL- . PLIST . , , .
PLIST PHP, Python, , Java .Net.
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