Dual codes refer to health codes and travel codes. The health code is based on real data, which is declared by citizens on the Internet. After background review, the personal QR code can be generated. As an individual entering and leaving electronic certificate locally, the QR code can be declared once, which is universal in the whole city. The introduction of the health code aims to make the work of returning to work more accurate, scientific and orderly.
Communication Big Data Travel Card is a free inquiry service provided by China ICT Institute, China Telecom, China Mobile and China Unicom for mobile phone users in China. Mobile phone users can query all the city information they have visited in the previous 14 days through this service.