This app is a great idea with high production value, but it needs some tweaking. Unlocking the story is a great motivator to get out and walk and the voice acting and audio are well done. However, its as if the creators couldnt decide between audio that would accompany the walk and keep you going that way or just keep you going with the reward of a good story. The story is structured so that you are part of it - very cleverly done, too - and requires extensive walking with all kinds of encounters as you proceed along the fictional route. But the audio clips are not long enough to keep you engaged as you actually walk. What this means is that you walk while playing some other audio, or nothing at all, and later, at home, listen to the unlocked clips (or save them for the next walk). Then you find yourself at home listening to an endlessly unfolding walking adventure that is limited by the walking story structure. I would say to the creators, choose: either a walking story that keeps you company as you walk, or get rid of the structure and just let us unlock a really good original story that may have nothing to do with walking.
Like others, I find that one has to fiddle to much with the screen to find objects on the map, alter the map route, and worst of all are the find the sentry games that require you to draw a path and gives no audio reward, just "badges." I am so tired of all the meaningless badges apps "award." I ignore many of these. Although occasionally one unlocks a piece of audio or little visual tidbit that adds dimension and fun to the experience Id go crazy if I cared to unlock all of them. Despite all of this, I would still recommend the app. Well see how the story turns out.