I. Coding Challenge and Writing Prompt
Timed exercise completed using the Codility tool. I found I benefitted from doing some practice problems on Codility the day before I took the challenge. From what I've seen, most candidates are eliminated during this round. The algorithm is not unreasonably difficult, but make sure you test your solution carefully, including edge cases. Take the written component just as seriously.
II. One Technical Phone Interview
Hour-long technical question with a current engineer, going further and further in depth with various optimizations. After the technical portion, there will be an opportunity to ask questions. I read that some people had two or more technical phone calls, not sure if that's changed.
III. On Site
They fly you out to SF and put you in a really fancy hotel for one night. This was a bit of a culture shock for me... while the dress code at LiveRamp is casual, I was glad I brought a blazer for the hotel. The interview lasts most of the day, and in my case consisted of four separate technical white-boarding exercises, each supervised by a different engineer or pair of engineers. You can pick your own language; I would recommend using Ruby or some other language with whiteboard-friendly syntax (don't make my mistake and use Java!).
IV. Follow Up
You'll have a chance to follow up with your interviewers about the algorithms you worked on during your interviews. I didn't really finish any of the exercises on site, so this part was crucial for me. Expect to have meaningful followup conversations even after you have submitted your "final" solutions.
The whole process was fast-paced and very efficient. I felt like LiveRamp was honest and straightforward with me the whole time. No mind games or other tricks. Everyone I spoke to was friendly. I suspect that your level of technical knowledge is less important than your willingness to explore problems in depth and your ability to communicate your thoughts to the interviewers.