The interview process has several steps.
First, there was a phone interview with the HR assistant. We were talking about the position, my experiences, my motivation. It was very useful, and after that, I get an immediate feedback.
An online test followed on hackerrank. It was interesting, with a lot of different questions, but not so complicated. I liked it.
Next round was a Google hangouts meeting with 2 lead developers. We were talking about the product, the technical challenges, and I was also challenged by an online coding task. They were kind and open, and I could ask questions also.
Again I got a feedback very soon (after about an hour) that I can proceed to the next step with a product manager. For that, I got a detailed description of the objective and the potential questions, which was really useful.
The interviewer was friendly, the questions and topics were challenging.
I got a positive feedback again very soon.
Last round was planned to be with the VP of Engineering and one of the co-founders. Unfortunately we could not find a proper time that would fit for all. Finally I was talking to the VP and one of the lead developers.
We were talking about the motivation and there were a lot of technical and architectural questions.
This did not work out as much as I expected, so finally the process has finished at this point, my application was rejected:(
Anyhow, my overall impression is really good. The organization of these interviews was very professional. For each interview I received a detailed description so that I could prepare for it. The appointment was coordinated with an online calendar.