You can hail a taxi on the street, but explaining the address without Chinese is hard. In DiDi you drop a pin, see the price up front, and the driver follows the navigation.
What DiDi can do
Step by step
DiDi works three ways: as its own app, as a mini-program in Alipay, or as a mini-program in WeChat. If Alipay is already set up, you may not need the separate app.