The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
All you have to do is carefully plan your route. You can see the whole map, but your possible directions are marked by the arrows on the ground. More often than not you will have a chance to choose where to go. But to make it more interesting sometimes the direction is predefined.Slide your finger or just tap the screen to which side you want to go.Good luck, and don't get lost.