There were a total of four rounds. Three of them were on-campus, face-to-face interviews in Bangalore. The first round was a telephonic round based on simple data structure and algorithm questions. The focus was on the approach, not the final solution. In fact, the interviewer helped when I was stuck. The next three rounds were face-to-face. I was flown to Bangalore, and they paid for the hotel expenses, but not other expenses like commuting (even though the email mentioned they would).

The telephonic round was entirely based on DS & algo. I don't remember the exact questions, but preparation from GeeksforGeeks is enough.

The on-campus questions were based on iOS. Even though the preparation material they gave covered only DS & algo, I was expecting more of such questions.