I completely back this up.

I've also never heard of anyone using Uber, though it is an option and I'm sure a few do.

Didi and Kuaidi are by-far the leaders, completely entrenched. I think first-mover advantage will be the case here. The big thing these services are now competing on however is not hailing a ride, it is providing financial services through the app. They're no longer ride-hailing apps, they're finance apps with the option to hail.

[Perhaps a big difference with Uber compared to the US, is the use of it by taxis. Almost all taxis are on Didi/Kuaidi (indeed, these were taxi-only services at the start) and taxis are inexpensive.]