Abstract: In an embodiment there is provided a computer implemented method of controlling a user interface responsive to user engagement with a displayed game area on the interface, the method comprising the following implemented by at least one processor of a device, displaying a game area having a plurality of first game objects on said display, providing one or more characteristics of said first game objects and one or more action characteristics of at least one second game object, displaying said at least one second game object at a position on said game area, detecting user input re-arranging one or more of said first game objects, and activating said action characteristics of the at least one second game object in dependence on said detected input re-arranging said one or more first game objects to provide a sequence of two or more first game objects having one or more of the same characteristics adjacent the position of the second game object, and wherein at least one of the action characteristics of the second