Golden Sum app for iPhone and iPad

Golden Sum is a number puzzle game played on a 5x5 grid. You start with two numbered beige squares, a 1 square and a 2 square. To create new squares you select any beige squares that share a side, then select an empty square that shares a side with one of the previously selected squares. The sum of the two squares becomes a new beige numbered square. Then you can use the new square to create more squares, with the end goal being to change the gold square into a beige square while keeping the same number.

Sound confusing? Theres a step by step how to play in the game.