"cal-coola": Simple brain challenge for all: ▷ 6 numbers, 4 operations... and 1 goal result ▷ Work out the goal result, or a close one ▷ The sooner you solve it, more points you get Incredibly easy to play: ▷ To calculate: Drag two tiles into +, -, ×, ÷ ▷ To undo: Double-tap on the tile ▷ To finish: Drag tile to the target box