Even though there's no official definition, cities in China are often informally slotted into four tiers. In general, higher-tier cities are larger and wealthier compared to lower-tier ones.
Think of a city in China, and the image that springs to mind is likely Shanghai or Beijing. But there are over 100 cities with a population of 1 million in the country.
Far from being focused in a few huge megacities, China’s internet population is almost evenly split between the big cities and the smaller cities. And the two are also evenly split in other ways: The apps you use and even the phone you own will likely be different depending on where you live.