**This version of 21 Pro: Blackjack is enabled for iOS 4 only to allow iAds. The paid version does not have this restriction and can be run on iOS 3 . Created by true blackjack enthusiasts, every detail in 21 Pro has been painstakingly crafted to provide hours of entertaining casino-like play. Look at what others are saying about 21 PRO Blackjack “Pro 21 Blackjack is Awesome” says APPCRAVER Various iOS4 fixes including leader board/cash out. Removed advertising during shuffle.