Some Allwinner devices come equipped with GSM, UMTS or LTE modems providing mobile data. Other devices have SPCI connectors, or you might just want to connect a USB dongle.
This mobile modem is available as an SPCI module, which is a new formfactor which Huawei seems to be pioneering.
SPCI is Smart Personal Computer Interface, but it is marketed as "UltraStick" by Huawei. SPCI is basically a connector with USB2.0, PCM (for audio) and some extra power handling. It allows for both data and voice mobile communication. More information about this format is available in this datasheet.