I was referred by a friend who has a job there. I applied online and was contacted for a telephone interview. The telephone interview was quite relaxed and more like an informal chat with a HR guy. Following that I was invited for an interview day at their Abingdon office. The interview day began with me arriving half an hour late after my alarm didn't go off - whoops. I phoned them before arriving, and they were very understanding and told me to still come for the interview. Upon arriving I was introduced to a few people, and then given a programming task to complete. The programming task was fairly trivial and could really have been finished within an hour. As I was given the whole day to do it (more or less - 10am until 4pm with a couple of hours taken for lunch and being shown around), I went overboard with my solution in an attempt to impress. At 4pm I told them that I had finished my solution, and a couple of guys came over to have a look. They played with it for a bit, tried to break it, checked my code, questioned me on various bits of code. Thankfully, despite being probably over-complex, my code didn't fall to bits. Make sure that you check for invalid inputs, as they seemed keen to make sure that it wouldn't crash with an invalid input. After that I gave a short presentation to someone, and then had another chat with the HR guy. He discussed various terms of the contract, and I explained that I had another offer with a deadline.

It was friendly. They asked about my coding experience, my job experience, internship experience. They talked about the company culture and encouraged me to ask questions to them as well. Overall really positive experience.