You can always use both. You can set over to use its own navigation system and turn off the sound, and then run maps or Waze in the background, pull them up, and put the address you're going to in verbally. I used to do that all the time, and choose the route that would make me the most money.
One of the features that I liked about Waze is that you can actually tap on the bottom bar and then on routes and adjust the route that you're taking according to what will give you the most miles and save you the most time. This sometimes changes halfway through your trip. Just make sure that you tell your passenger that there's traffic up ahead so you're checking for a faster route for them to get to their destination. I used to get tips specifically for doing this, and you cannot do it using Uber Maps.