All apps that can filter calls and SMS are not available on the App store. Only available for Jailbroken iPhones.

Call and SMS filtering:

• Pysl: It is free but did not work well for me. The UI is clunks
• Mcleaner: This worked. UI is not very intuitive but ok. Has a 15 day free trial
• iBlacklist: Havent tried it. Trial version can block limited number of numbers (2!!)
• SMS2Mail: Free app to email SMS messages (Cydia Categories->Messaging)

Chess and other games:

• Black and White: Reversi for iPhone. App store (FREE)
• Chess Puzzles: Free iTunes store app with 50 puzzles
• Chess game and Chess puzzles from Shredder (FREE). Excellent puzzles refreshed every day.
• Tetsuki: Allows you to connect and play on GO servers (GO, Baduk, WeiQi)