XXI: 21 Puzzle Game is an engaging and challenging puzzle game available on the iPhone. The objective of the game is to create rows and columns that add up to 21. With 200 unique and challenging puzzles, players will have plenty of opportunities to test their skills and strategize their moves.

One of the standout features of XXI: 21 Puzzle Game is the inclusion of a special gem that can be either a 1 or 11, adding an extra layer of complexity to the puzzles. As players progress through the levels, the puzzles become progressively harder, ensuring a continuous challenge and keeping the gameplay fresh.

The game also offers Game Center achievements, allowing players to earn recognition for their accomplishments. Additionally, there is a leaderboard where players can compete for the highest level achieved. The beautiful music, sounds, and retina graphics enhance the overall gaming experience, while the universal app ensures that the game looks great on both iPhone and iPad.

For those who enjoy sharing their achievements, XXI: 21 Puzzle Game allows players to share solution photos with friends. With its intuitive gameplay, challenging puzzles, and social sharing capabilities, XXI: 21 Puzzle Game is a must-play for puzzle enthusiasts.