Hi Guys,
Mercury Minds has developed an X-Cart connector for MobiCart enabling native as well as web apps.
http://support.mobi-cart.com/entries/20860417-x-cart-plugin-now-live-in-beta
Please feel free to pop over, we'd be more than happy to send you the files and answer any questions you may have.
You can also request new features which we will do our best to include in a future release.
Thanks again,
Wladimir