First of all, take into account that the smaller the board is, the easier the game. Go is a territorial game for two players (black and white) where the goal is to protect each one’s territory and at the same time, attack and capture the opponent’s stones. The instructions are pretty long and detailed so if you don’t really know how to play we recommend that you take a look at them.
You can always view the settings, which means that the board size, the rule set and the difficulty can be changed. There are three sizes available in the full version and 10 difficulty levels in total. The game can be quite hard to get the hang of it but once you get used to it, it’s a very recommendable application for exercising the mind.