I've always wanted an app like this. It's something I wish I had thought of first. I work in NYC and have been playing it over the last week when I have time, and even when it took me places I thought I knew it showed me things I never noticed. The stories are great, entertaining and informative. However, the app itself is a bit buggy and parts of the game are really frustrating. For example, if I ever lose my connection (say, in the subway), and open the app, it says it can't find my match and I have to completely close it before it will pick it up again. I once opened it up in another city entirely and it told me I was in the right place. Then, when I was right next to the building I was looking for, it said I still had a while to go. Submitting an answer to one of the riddles is painful -- the panel keeps closing while I type, and then when I finally hit enter it has to send it to some server to verify so it takes a few seconds of basically being frozen. (Why can't it check my answer on the device?) The riddles themselves are the worst part. It's like they get you to where you need to be, then choose something completely random and impossible to answer correctly for the riddle. (I'll avoid spoilers, but let's just say it gets frustrating the third time you have to stand in front of a building and count the shapes in a window when half of them are covered by construction.) Why not ask questions about other notable buildings nearby? There's also a pretty glaring language problem that's understandable but frustrating. It seems like half of the app wasn't translated from Italian, and at least four times I got a message or saw my stats or something where I couldn't understand them. All that said, there's huge potential here. I would absolutely play again, and I would pay for additional content if it comes out. But I really hope the app itself keeps improving, too.