Zillow Senior Software Engineer - IOS interview questions

First call with the recruiter. I would like appreciate him because he was friendly and always one call away whenever needed. After that screening interview which includes one algorithm followed by the iOS related questions. On-site interview: Round 1 - Algorithm followed by the behavioral questions. Round 2 - Algorithm followed by the design patterns and knowledge of ios. Round 3 - Algorithm followed by the behavioral questions. Round 4 - System design followed by the behavioral questions. All the interviewers were helping throughout the process. They will also give you hints. Key is think aloud when you are working on your algorithm.