From Yoshitaka Nagano:
Summing is a mathematical puzzle game. Your goal is to remove the tiles on the playing field by placing other tiles. You can do this by only one method: if a placed tile's number matches the sum of some neighbor tiles' numbers, the placed tile and the neighbor tiles are removed. You can place the top tile from the left column on any empty square.
What's new in this version:
Fixed the version number in the launcher info window.