Amazon has a several stage process. My phone screen included a simple coding problem on a shared screen so the interviewer could watch what I was doing. NDA prohibits me from offering details, but it was intended to test my understanding of data structures (in this case a heap) and computational complexity (O(n) solution found). I was a little taken aback but the coding question for a PM position, but Amazon PMs are highly technical. I was called in for a round of 5 interviews, all of which were SDEs, which again took me by surprise as I was interviewing for PM. There were several programming problems and one that was more about software design. The interviewer had me solve a real-world issue they had on the Kindle team. But most questions were STAR format scenario questions. I had a bunch of scenarios ready, but very few of them fit the questions. I realized after that we were really looking for different roles and didn't match well. Everyone was very pleasant. It looks like a really exciting place to work.