The classic paper and pencil game now in an android version.
for all of those who haven't played the game yet here is a short description of the rules:

the game objective is to create as much as possible S.O.S sequences either diagonally, vertically or horizontally.

the game can be played against the computer or against another player. it is played on a NxN grid.

and the most important rule is to ENJOY!

Screenshots: