Don't know, but this is what Wikipedia says about it:
Professor Layton's London Life (レイトン教授のロンドンライフ) is a 100 hour RPG developed by Brownie Brown. The game features many of the Professor Layton Series characters, from all four games released as of 2009, and three downloadable characters from Professor Layton and the Eternal Diva. The game allows the player to create his/her own avatar that they can have live in London. Specific Londoners will ask them to do certain tasks, unlocking more places in London to visit. The game has been described to have graphics very similar to Mother 3, and it has been said that London Life is a sneak peek for a new Level-5 game, Fantasy Life launching in Japan during 2011. Level-5 announced that the US localization will include London Life, and as a bonus will, as opposed to the Japanese version, be available before the completion of the main game.