I have not but my co-founder worked at Uber for 5+ years. He said they had engineers basically building whatever anyone wanted. He said they built their own Slack more or less just because they could.
Data quality issues, like missing tolls, intersection being different on Uber's map than in real life means that Uber is underpricing drivers, which leads to driver cancellations. It was very frustrating for me to start the whole process again mutiple times after waiting 5-10 minutes and try to haggle with the drivers all the time.