Right before Christmas, Xiaomi introduced the Mi Notebook Air 4G in Xiaomi's home market China. Except for a processor upgrade on the 13.3 inch version, the machine is exactly the same as the version released in July of this year, except for an integrated LTE-module from China Mobile.
http://www.notebookcheck.net/Xiaomi-and-China-Mobile-present-The-Mi-Notebook-Air-4G.188943.0.html