Apple Optical Engineer interview questions

Video interview with the manager the week after my application and lasted 30 mins. Quite relaxing chat on what they do and my background. He also warned me I could get 6-8 more interviews, but I just got only 2 more two weeks after at the same day (45 mins each). Here the questions were more a bit technical mostly related to my background. Two days after the recruiter in charge of the process told me they don't want to proceed any longer they don't provide feedbacks.