I was contacted initially on LinkedIn for a full-time position after my expected graduation. After some brief conversations with the recruiter about what I was interested in doing, we moved on to 2 rounds of 1-hour phone interviews. These were done with an engineer, then a team manager at the company, consisting of 2 technical questions (collab on Google Docs) and some personal background stuff. These guys move fast, I received feedback much quicker than I anticipated, but they're willing to work around your schedule. There was a whole week in between my 2 phone interviews, due to various deadlines I had for school. The recruiter was very understanding about accommodating to that, which helped take the stress out of the situation.
After those calls, they flew me out for a day in San Francisco for some 1-on-1 interviews with engineers at the company office. This consisted of 5 45-minute sessions that began in the morning till the afternoon, interrupted by lunch. These weren't trick question interviews, at this stage they really just want to see if you're competent and a good fit for the company. They asked practical and useful stuff, so if you've got good fundamentals (e.g. data structures, trees, running time analysis), things shouldn't be too difficult. A lot of the questions were pertinent to what that interviewer is working on (or has worked on in the past) for the company, so there's no worry about having to jump through hoops or run through theoretical situations that have no practical value. The only "unpredictable" thing is to be prepared to back up what's on your resume. They won't grill it to purposely try to find blind spots in your knowledge, but they will assume you have working level proficiency, and ask questions accordingly. After a lot of algorithmic questions, I got hit with an HTML/CSS question. It wasn't hard or a "gotcha", but it caught me a little off-guard to go from recursion to markup syntax.
Overall, the experience was very positive. The interviewers will take some time and have short friendly discussions with you based on their roles in the company and what's on your resume. So if you're strong in certain languages (Java, JS, Python, etc) or a specific aspect of software design, that would be the time to flaunt it.
The recruiter was also approachable and pleasant to work with. She was very helpful and made the entire process seamlessly smooth. Sometimes you'd email to ask something in the evening, and receive a response only an hour or two later. Ultimately I took another offer, but I would love the opportunity to work with them in the future. AppDynamics is definitely a company to keep on your radar.
P.S. they have amazing snacks/drinks lying around. The alcohol alone is a perk if you ask me.