Applied through my college's career database.

Had a short phone interview with a recruiter. The phone interview was pretty straightforward, until the end, when I asked to talk through the design of a hypothetical Google Glass app.

The next round was an online aptitude test proctored by a third-party web proctoring company. It was intended to take 3-4 hours and involved open-ended programming questions and basic SAT-type math questions.

Apparently, I either didn't do well enough on the test or took too long to finish it.

The aptitude test was the most difficult part of the interview process. I honestly don't remember the questions since it's been almost a year since I took it.