Harbor Operator is a drawing simulation game. It tasks the player to manage a shipping lane at fictional Coastal Cove, Anchor Point and Port City locations as a harbor master. To direct traffic, they must draw a line between each ship and port, or from a ship out into open water. Their goal is to achieve the highest success score.
The game challenges the player with high traffic in narrow waterways and color-coded ships and ports. If the player fails to handle the traffic around the ports carefully and with precision timing, they must restart the game or view an ad to continue.
The player receives a warning before a ship enters the shipping lane. The game displays a yellow triangular sign marked with a black exclamation point at the position where the player can expect the ship to appear on the screen. To make it easy for all ships to use the lane, they must quickly draw a line between a ship and port and then away after a red timer counts down.
Harbor Operator ends the game if any ship at any point crashes into another ship. This means the player can lose the game if they direct a ship away from a port after they helped it dock, and it then hits another ship entering or exiting the lane.
It also allows the player to skip a difficult scenario with the fast-forward, double-arrow button at the lower-left corner.