I first saw the 2850 installed in my friend's car & I saw it had waze integration. I decided to have one for my wife's car. At first, the waze app didn't show in the head unit, & I couldn't figure out why.
Then when I had steering wheel done by seatmate, they disconnected the battery so as not to accidentally deploy the airbag. When it was connected again, the waze app already showed in the head unit. Maybe you also need to remove the terminals of the battery to reset your head unit & hopefully the waze app would now show (you need to open the waze app so pioneer would add it to one of their apps - see pic below).
For Spotify, yup it can integrate with the 2850 head unit. You can control it too via the head unit or steering wheel controls as well (see pic below).
