The entire process consists of four steps:

1. Answering questions on a company's page
2. Skype interview
3. Home task
4. Interview at the office

On the Skype interview, we discussed Objective-C, blocks, and memory management. The home task was to build a simplified analog of a Yandex.Disk client for iOS. The offline interview took approximately 6 hours, and we discussed a bunch of topics covering the entire computer science theme (algorithms, design patterns, multithreading, iOS platform, etc.).

It's hard to remember any particular questions because it took place a couple of years ago. In general, you should have strong knowledge in every topic mentioned earlier.

Design an architecture for a Tetris-like game.