Indeed, Uber works*, local cab apps don't. Attempting to use the one for our local firm just means Diane from the office calls.
Grab, the alt-Uber that's ubiquitous in SE Asia, has a cool feature where it translates the messages from the drivers into your language (sometimes, it's a bit variable), but it evidently uses Google Translate, so a lot of them up get happy frog!
I text back English?
No, Vietnamese! comes the response.
*unless your driver falls asleep.