== 1. Does Caissa chess implement [http://en.wikipedia.org/wiki/En_passant "en passant" rule] ? == Yes Caissa chess implements it, as well as any other chess rule known to [http://www.fide.com/ FIDE].[[br]] Please check [http://youtube.com/watch?v=ZUJMT8AsFZ4 our "en passant" demo] on youtube. == 2. What is the strength level of Caissa's chess engine ? == We estimate the engine is capable of rendering decisions at 1900-2000 [http://en.wikipedia.org/wiki/Elo_rating_system#Elo.27s_rating_system_model ELO] level. This engine was designed to perform on mobile platform, with power efficiency in mind. We are working on [http://en.wikipedia.org/wiki/Candidate_Master CM] mode, which will make Caissa significantly stronger. == 3. Do I have to pay for subsequent update ? == No. If you purchased Caissa Chess, you are entitled for bug fix updates for the lifetime of the application. Meaning any 2.x updates will be free of charge. There is big feature 2.1 release coming. It will come free of charge. == 4. How does AddressBook integration work? == It takes email address of your opponent and if it's exists in your addressbook marks it as ChessPlayer. If it doesn't exists it add new contact to AddressBook database and places into the group ChessPlayers. As a result, you have all your chess buddies aggregated in the group ChessPlayers. If you deselect AB integration, it will remove all information it added to your AddressBook. == 5. If I need support, how can I reach someone in Caissa Dev Team == [mailto:support@caissa.us]