People ask me how Chinese managed to control COVID for the last few months.

Well, people there have to run mobile tracing apps on their cell phone 24/7, which generates a pass for them to access any transportation, restaurants, malls, hotels etc.

A relative of mine recently did a sight-seeing trip in China, and ended up having to run 4 tracing app on her phone.

One from China CDC
One from the cdc of the province she lives
One from the cdc of the destination province
One from the Hubei CDC for her 5hr layover in Wuhan

If any lab-confirmed covid cases has came in close proximity of her, the tracing app will turn red automatically as soon as the lab report comes out. And anybody who contacted her would have the tracing app turning orange.

People with red-status will need to quarantine at home for 14 days, as geo-tracked by the cell phone.

This measure will last until most people got vaccinated in China.

Not saying the same measure is doable in other countries. But they are taking extraordinary measures.

Here is an American perspective of what China has been doing to keep covid at bay