There are a couple of popular options to add mobile interface to X–cart based store which will allow your customers to browse products and place orders on mobile devices faster and easier:
1) X–Cart Mobile Extension – this is an extension from developers of X–cart. Easy to setup and manage solution compatible with most mobile platforms.
Details: https://www.x-cart.com/extensions/modules/x-cart-4-mobile.html
Demo: http://mdemo.x-cart.com/home.php (visit from your phone)
Price: $249 for license and $75 installation
Details: http://www.thexcartstore.com/xmobile-smartphone-mobile-xcart-template.html
Demo: http://demo.thexcartstore.com/xmobile/home.php?txs_xmb_key=xmobile (visit from your phone)
Price: €99 for license plus $75 installation
– Finestshops.com offers managed e-commerce for medium and large stores based on Magento or X-Cart Shopping Carts. Find out more at www.finestshops.com