Can vivox3l make calls and send text messages using China Unicom 4G?

You can make calls and send text messages. If you are referring to vivo X3L (mobile TD-LTE version), it supports mobile 4G. It does not support China Unicom 4G, but supports China Unicom 2G. The specific network standard: Mobile TD-LTE (Mobile 4G), Mobile 3G (TD-SCDMA), China Unicom 2G/China Mobile 2G (GSM), and China Unicom 4G card are inserted into this mobile phone, and the 2G network can be used. Making calls and sending text messages will not be affected.