Four Cards (24) is a popular card game in China. It is often played as a competition or to develop basic math skills. 4 cards are dealt and the player orders them and 3 math operators to equal 24.
Four Cards is available on Android Market for free.
To play, drag the cards and operators (add, subtract, multiply, divide) to the chosen positions. Each card can only be used once, but math operators can be repeated. Only whole numbers zero or greater can be calculated.
Tapping on a card or operator places it in the next open location from left to right. Tapping on a card or operator in the equation removes that item.
The numbered cards are equal to their face value with "A" = 1, "J" = 11, "Q" = 12 & "K" = 13.
Picture below is an example of a completed game.

Resets the current game to its initial state.
Starts a new game.
Shows the solution of the current game.
Displays help instruction
Exits the game Twenty Four.