Getting cell phone service with a data plan is useful to have in China when WiFi is not available.
Internet access is extremely useful in the street especially for translation apps and texting.
Some places with free WiFi, for example at some McDonald's restaurants, require a local telephone number to connect to and use their WiFi.
There are three major mobile cellular service providers in China:
- China Mobile
- China Unicom
- China Telecom
Each requires a passport to get a SIM card.
China Mobile offices are the most common and are everywhere but some locations will not accept a passport and will ask for a Chinese ID card.
China Unicom is the recommended service. They have a monthly plan with telephone and data for 100 CNY and they readily accept passports as identification.