I had couple of phone interviews with different teams. My read of LinkedIn is that they require prebaked people in their technology stack. This is something big companies (like MS/Google) do only for contractors. For full time employees its always a long bet to hire great people who have the interest and potential to grow the company. My first interview was with for mobile phone dev. The person was very nice however was very disappointed that I don't know javascript (my resume does not even have JS written as a skill). He asked me to find an element in a sorted array which I did correctly to his satisfaction. But, expectedly, the recruiter said team does not want to move forward. My second interview was for backend dev. I know java because of my android background but I am a .NET person. The interviewers expected someone who is great at Java. Any ways in one hour first there was tech screen questions on Java. Then they asked two questions which I think is flawed because the interview and interviewee are both rushed. First one was really easy (one of those on glassdoor). Second one was to write a deep iterator. This is a tough question to complete in 20 mins (I mean to think the algo and write code). Also, I felt the interviewer was rude. This was a pass/fail question for him (write code for me or hang up the phone kind of attitude). Only plus point is that their recruiters are really nice people.