Is Apple's interview difficult? Yes, of course. The on-site interview at Apple is by far the most difficult and deepest one I've ever have in my career. Yet it is also the most professional one. Don't get me wrong, the interviewers are not going to ask you any strange IQ questions, but every question they ask is related to you future job and your current jobs at Apple, and your current job, assuming you are putting honest and correct information in your resume. So be prepared and honest. Speaking of interview process, it was just normal for me. A couple phone interviews then a full afternoon on-site. No lunch interview so be sure to load up yourself. Bring a chocolate bar with you. Be prepared for long waiting after interview. It takes me more than 2 month until I got my oral offer, then another 2 week for the official one. I though it was just my case, but it actually happens to every one when I ask.

HR Screening, Interview with Manager, and a series of panel interviews. Lengthy interview process but pretty standard to most interviews today. Got to meet a great team and had conversational interviews