XML is a widely used format, even in the mobile world, where t became the standard for communicating between device and web server or web service.

There are plenty of parsers out there, here is a good comparison about them:
http://www.raywenderlich.com/553/how-to-chose-the-best-xml-parser-for-your-iphone-project

I have tested out TBXML, which has very good results in reading and parsing, however XML writing and creation is not supported.