IonGrid got interested in me when they were acquired by NetApp, which means that, effectively, it was more NetApp interested in me than IonGrid. I say this because IonGrid is a small team of very talented (you can really see it from talking to them) engineers who were able to make a revolutionary product and manage to get acquired by NetApp.
First there was the interview with the recruiter. Regular BS (yes I do get annoyed from talking to recruiters). Then followed the interview with the hiring manager who used to be CTO at IonGrid. It was a very pleasant conversation. Then there was silence, for a month. After a month another NetApp recruiter contacted me and asked me if I was still interested. I said yes and the on-site interview was scheduled.
I was scheduled to meet 4 people, but ended up meeting only 3, the 4th one was very busy, working on a release, so he couldn't meet me.
The first engineer was an iOS developer, and even though I did not have any iOS or mobile development experience, he decided to ask me mobile development (and especially iOS) questions regardless. I obviously used logic and my best guess to answer them. Overall he seemed like a nice guy. But at that very moment I also realized that I am not a good fit at all in the team because I simply do not have the set of skills they are looking for.
The second team member was a founding member of the company. We had a little conversation in the beginning then moved to the technical interview. It was a very trivial question that I got 80% right.
The third team member was once again a founding member of the company. The technical question asked was the same as the ones posted on here. I will also post a solution to it, and hopefully they will not ask the same question to other candidates. The reason being is that it does not really test your knowledge of computer science. Its more of those types of problems that if you have solved them in the past, you will be able to solve them, if not, you will endlessly struggle. I was able to code it with a few hints from the interviewers, but it still was not the same as his answer. So, very, very similar to the interview experience of "Mobile Software Engineer" posted on this website.