A client device with processor(s), memory, and a display captures an image of a displayed interface of a game being executed on the client device. The image includes game data corresponding to game performance of a user of the client device. The client device provides, to a server, the image for extraction of the game data from the image of the displayed interface of the game. In response to providing the image, the client device receives, from the server, game ranking information specifying a ranking for the user that is based on the game data extracted from the image. In some embodiments, the client device displays the game ranking information in an interface of a social networking platform, where the game ranking information includes relative rankings of the user and social network contact(s) of the user on the social networking platform.