1. A method performed by data processing apparatus, the method comprising: determining frequencies that a user communicates with people; detecting at least two faces based on image data in a live image feed of a camera of a mobile device; determining that the at least two detected faces correspond to at least two people, in a set of people, who are classified as being important to a user; in response to determining that at least two of the detected faces correspond to at least two people, in the set of people, who are classified as being important to the user based on the frequencies that the user communicates with people, determining one or more quality scores for the at least two detected faces that are determined to correspond to at least two people who are classified as important to the user; capturing multiple images of the detected faces corresponding to at least two people, in the set of people, who are classified as being important to the user with the camera based on the one or more quality scores, wherein the capturing is ended in response to determining, based on the one or more quality scores, that a face image having at least a minimum quality score has been captured for each of the people classified as being important; and generating a composite image that combines the multiple images of the detected faces corresponding to the at least two people, in the set of people, who are classified as being important to the user.