Iris runs through Cha Cha, so as you can expect some specific questions don't get the right answers, I'm sure half of the questions are either in the cha cha database and harder ones are answered by Cha Cha Vetters. This app still needs alot of work. As for right now I prefer Dragon GO! Can't wait until Google releases their siri clone.
Iris is in Alpha. The developers wrote the program in 8 hours apparently. This is what it stand for "intelligent Rival Imitation of Sir". Im sure once more users download it and ask questions, the app will become more usable. It is in the learning stage now and it has a lot of potential to take on Siri.