I found thanks many friends the site http://www.whaiwhai.com
Basically whaiwhai “is an interactive story that will lead you to explore a city in a new and exciting way. Prepare yourself to look for clues and discover hidden places: whaiwhai is a treasure hunt.
As you play, you’ll discover original, exciting aspects of the city you’re visiting. You’ll learn about ancient tales that will guide you on a path full of mysteries and legends. You’ll have puzzles to solve and clues to follow in order to reach your goal.
Each city has a different treasure, and finding it will be an exciting experience. Whaiwhai combines history and fantasy: you’ll step into the script of a story that plays out inside the city and you’ll even get the chance to become one of its heroes”.
They started from Italy in some of the best cities in this country as Rome, Venice and Florence.
To play, you just need a notebook and a mobile phone.. and soon there will be a digital version for Iphones..