Well we've been building for about a year. Although the front-end is pretty simple it's quite complex in the back-end. We were the customers, myself and John both ran consulting web/dev companies. A lot of the user testing we did was on my mother 78, and Johns dad. We wanted to build a prod that didn't require any training. So if 'Mum', and 'Dad', could use it we knew everyone else could. In the last month we've been tweaking based on user feedback though, but not a lot. We'll be bloging about what we did.