This is a tile-laying game where each player gets to build his or her own castle room by room. There are 75 different room tiles, and in a way the game resembles Carcassone in that players are trying to figure out where to place what tile and how to orient it so it connects to other rooms. It is similar to Suburbia but castles build cities any day in my book. The mobile version will allow any combination of 2-4 human and AI players but there will be no online multiplayer mode at launch (the way the game plays makes async a bit of a pain).
The game improves on the single player campaign of Suburbia by mixing solo levels with levels against the AI, which should provide more variety and a more interesting challenge. And for those who enjoy European history and geography, the game includes many historical details about the real-life castles that inspired the game. Castles of Mad King Ludwig should be coming soon (it's already been submitted to Apple), and it will probably cost somewhere around $6.99 or so.