Applied during Apple's special on-campus career event at school, had interview on campus the next day. Then, had a few phone interviews with various teams in Apple. After that, one manager asked me to do an on-site in Austin.
The on-site interview has 6 rounds, 5 of those are technical. They asked about out-of-order execution, hazards in pipeline, cache designing, basics of C/C++ (read the code only), REGEX, what is hold time and what is setup time (no questions on timing analysis though...) the projects that I have been working on, how to verify a digital design.
The managers and employees are really sharp. They know what they're doing and they can think while you describe your solutions and the projects that you've worked on, even on the projects that they're not familiar with.
The following questions were asked during on-campus interviews.