How's the Uber service in Hong Kong...esp from airport...
In general, not cheaper than taxis, and often significantly more expensive.
I'm sure it works, but has some serious disadvantages over taxis.
1) the legality is in question (many drivers operate illegally as they don't have a hire car permit).
2) the pick-up point is a fair walk away from the terminal.
3) you have to pre-book your ride - if only upon arrival, so make sure your phone has battery. There is free WiFi at the airport, but as soon as you leave the airport terminal (on your way to your ride) you lose that connection.
1) fully legal.
2) pick up points a few minutes from the arrivals hall, next to the terminal building.
3) just jump into the first available - there are always lots of taxis waiting. No worries about prebooking or finding the correct vehicle.
The only minor advantage of Uber would be the credit card payment. Taxis take HKD cash only.