When the mobile phone uses the Unicom card, it does not display the Unicom logo, which is influenced by the system identification and support of the mobile phone terminal, and has nothing to do with the Unicom number itself. Displaying the name of the operator is a basic function supported by mobile phones. Most mobile phones will automatically search operator information according to the accessed signal. In Chinese mainland, the default sign is "China Unicom", but this sign is not fixed and can be modified or hidden in many ways. 1) cell phone language mode. If the mobile phone does not use Simplified Chinese, it will display China Unicom but other languages. For example, after switching to English mode, "China Unicom" will be displayed instead of "China Unicom" in network mode; Similarly, if other languages are used, the foreign language "China Unicom" will be displayed; 2) The system identification of some foreign mobile phones (parallel planes) and engineering machines is missing. Some engineering machines (for testing only) and foreign customized mobile phones do not have complete operator list data in the execution system, so if the operator used is in the default data, the Chinese logo of the operator will not be displayed. 3) Some terminals don't start the service of "automatic search operator", especially in the case of roaming in Hong Kong, Macao and Taiwan or international roaming, because they switch to other local networks when using, at this time, because automatic search is not started, they can't identify the accessed networks and become "unknown operators"; At this point, change the search mode and restart for recovery. 4) Modification of the mobile phone itself. At present, most smartphones can be jailbroken or cracked (such as the root of the desktop system). After obtaining the highest authority, you can not only change the font at will, but also modify some default logos, such as China Unicom, which can be changed to other logos. Here are some commonly used tools, such as using Fakecarrer software to modify the operator logo. Some mobile phones (such as Xiaomi) can be changed directly in the advanced settings without downloading additional software.