There were 3 interviews over the phone, two basic coding interviews and a system design interview. Two of them were with two engineers and one interview was one-on-one. The questions weren't difficult and they helped through the process if you have a bug or miss something.
The interviewers were very friendly, although sometimes there was trouble understanding accents. I pretty much had to type everything in one of the interviews because English was not the interviewer's first language and the phone call quality was bad.