A free app for Android, by LevelXcode.
Hack Test is an interactive simulation of hacker skills that uses simple logic, language, and math puzzles.
Playing puzzle games and solving puzzles improves our short-term recall, spatial reasoning, and logical thinking, all of which contribute to a higher intelligence quotient (IQ). It has been discovered that daily puzzle solving and puzzle game play can raise IQ.
Since there are no physical pieces in mobile puzzles, there is no chance of losing a piece while playing. You can find every piece and hint on your screen. It's extremely convenient because the game can be downloaded and played on your mobile phone.
