The
BbApp framework lets you skip months of pain on the repetitive parts of building a very expensive app for WordPress.
It includes an XCode project template and dozens of frameworks to tie them together ready for review by the app store.
You can use BbApp with WordPress alone or BBPress. To enjoy a fully-featured native app just download, build in XCode, and publish.
It also includes open-source PHP libraries that make it easy to integrate your existing native mobile application with WordPress.