The technical questions covered a wide range of areas which I appreciated. The areas included object oriented design, architecture design, problem-solving/algorithms, objective-c (blocks, view controllers, etc.), and mobile specific questions. The most difficult question I was asked was to design a document upload/fetcher system for mobile (kinda like dropbox for the iphone). The difficulty was really in all the details of the problem (caching, database modeling, security, sessions, etc). Algorithm questions ranged from binary tree search questions to array pattern searching. The most unexpected question was the interviewer gave me a stream of digits and asked me to find the pattern. I got really stumped on this problem, it was my last interview of the day and I just blanked out. I guess I did well enough throughout the day because I got the job. By no means an easy interview, but not extremely hard, I was extremely well prepared as I had been interviewing for a while. Id say its on the average to difficult scale, if you are bad at architecting systems then this interview would have been HIGH diff.
