Catan is a handheld implementation of a board game Settlers of Catan. There is a flat board with the game world divided on a number of hexagons. The goal of the game is to reach ten Victory points that are earned by having settlements, point cards and some other conditions, however there could be other goals in this version. Every turn players can either build roads, settlements and cities or expand onto over territories, which also produce different resources needed for construction. Resources could be either purchased for Settlement cards or traded with other players.

The N-Gage version besides the traditional board game rules, also features a multi-stage tournament and a quest-mode with a number of different objectives, like building the longest road or having the largest army, by the end of the game, or reaching ten points under a certain amount of turns. Most of the in-game actions are decided by the roll of dice and it is done automatically. There are ten different computer characters who has their own portraits and things they say during the game, if you are playing alone. Of course, there's a multiplayer option for up to four players as well. Also there's a short tutorial to grasp the strategy basics.