I applied online. The process took 2 weeks. I interviewed at Meta in Nov 2017
Interview
I got one phone interview. The interviewer was very nice and helpful, a bit of an accent, but understandable. The algorithms problem was not very difficult, but I spent too much time on it.
Interview questions [1]
Question 1
Find the dot product of two arrays knowing that >80% of the values are 0's (needs to be faster than one for loop O(n)).
I applied through a recruiter. The process took 4 weeks. I interviewed at Meta in Aug 2016
Interview
One phone interview. Another on-site interview. Both were extremely question-oriented. No talks at all about past experience, interests, or anything else. Disappointed that it was just a binary "Did you or did you not get the solution" type of approach.
I applied through an employee referral. The process took 6 weeks. I interviewed at Meta (Menlo Park, CA) in Nov 2017
Interview
Applied online, then got a referral from a full time engineer. About two weeks later, got an email with a recruiter to work out a time for a 45 minute phone interview, which got scheduled for 2 weeks later. Phone interview was 2 easy/medium coding questions.
The week after the phone interview, I got an email from my recruiter telling me I got an on-site, which got scheduled about a week and a half after that. The on-site was fun -- one 45 minute interview, same format as phone interview. Plus a tour, lunch, and Oculus Rift demo. One day later I got a call from my recruiter offering me the internship!