1st was a online test from IKM on C# and Javascript/jquery. Test was pretty good quality (this more complimentary of IKM than IRIS).
2nd was a 30 min phone interview with 3 people, some decent questions but overall a bit disorganised and lacking coherency.
Overall, to spend that amount of time/effort on an interview process without the case being made for why the candidate should consider working at IRIS is not helpful. The feeling I got was that IRIS aren't up to scratch in terms of interviewing developers, and thus probably not up to scratch with other operational concerns, making it not as good an employer as a lot of other tech employers in central London.
Interview questions [1]
Question 1
None really; but you might be asked over the phone to model the Pacman game.