I have created one app in iOS5.
I want to store and retrive data on web server.
For that I want to use JSON parser.
I have used demo given by ray wen
You may want to refer to SBJSON Framework which is frequently used for objective-C, I have used this framework in may of my iOS Apps.
You may get a reference about it from these links:
https://github.com/stig/json-framework
http://stig.github.com/json-framework/
Example Code: Also here is an example on, How to parse JSON with SBJSON Parser:
How to parse JSON into Objective C - SBJSON
http://jasarien.com/?p=428
Here is how you need to configure SBJSON into your app:
http://deshartman.wordpress.com/2011/09/02/configuring-sbjson-framework-for-xcode-4-2/
Hope this helps you.