What is the mas service of China Mobile Cloud?

China Mobile's MAS service is a service of China Mobile, which is a new service of mobile phone number (called "alliance number") jointly launched by China Mobile, China Unicom and China Telecom. Mobile office is a feature of large-scale services. Through "MAS mobile office adapter plug-in" and "MAS built-in mobile office module", the interoperability of alliance numbers among the three major operators is realized.