When I first got a call from this company, they placed me on hold as soon as I answered, mind you they called me, so I hung up. After that, they spam called me for about a week around the same time every day, so eventually I answered again and actually got a chance to talk to their recruiter, who is super awesome by the way.
You do a small phone screening interview with the recruiter, then they schedule you for an online technical interview. They'll send you a very vague study guide via email, and they'll give you about a week or so to prepare (depends on what date you selected).
During the actual interview, it gets straight to the point. It does not last any longer than 30 minutes and they try to get as many questions answered as quickly as possible. Also, the video interview is recorded, so the person that's interviewing you will not give you much feedback, but your recruiter will email you the next day when they have the results.
Just touch up on the study guide and it's main topics, and you should do fine. They do not expect you to answer every question perfectly. They want to know that you're trainable and at least have a decent understanding of basic programming. Most of my questions were in Java, but they did ask me some SQL, and HTML/CSS.