I store some data in my iOS app directly in a local .sqlite file. I chose to do this instead of CoreData because the data will need to be compatible with non-Apple platforms.>
Try those two solutions from Ray Wenderlich:
Exporting/Importing data through mail: http://www.raywenderlich.com/1980/how-to-import-and-export-app-data-via-email-in-your-ios-app
File Sharing with iTunes: http://www.raywenderlich.com/1948/how-integrate-itunes-file-sharing-with-your-ios-app
I found it quite complex but helped me a lot.