First had an online screening call which was straight-forward enough. The second stage is an in-person interview in Poole, Dorset. The company pays for your travel (and hotel if applicable) which is very positive. The interview day itself begins with a presentation about the company to you and the other interviewees. Then you have lunch with two of their employees who can answer any questions you have, and a short tour of the office.
The interview itself was somewhat strange, with a lot of focus on things that wouldn't really have an impact on the job (A-level choices, what universities you applied to, what you have been doing since you graduated [looking for a job?]). They also ask you what other companies you have applied to which is slightly inappropriate. It is important for you to have a strong motivation for the job, so have some stories ready as to why you want to apply for a job in software and some software-related stuff you've been doing since you graduated.
Overall a positive experience, however the final interview wasn't conducted very well in my opinion; your ability to do the job is secondary to you being software-obsessed and your ability to maneuver around slightly insensitive and out-of-touch questions as to why you haven't got a job yet.