A computer-implemented method comprising: receiving, for a first user of a social-networking system, from a plurality of contact-information sources, a plurality of instances of contact information, each corresponding to one of a plurality of categories of contact information; automatically selecting one of the plurality of instances of contact information in each of the categories of contact information as default contact information of the first user for use by a plurality of second users connected in a social graph to the first user, wherein the social graph comprises a plurality of nodes and a plurality of edges connecting the nodes, wherein a first node of the plurality of nodes corresponds to the first user, and a plurality of second nodes of the plurality of nodes each corresponds to a respective one of the plurality of second users, wherein: characterized in that the default contact information is selected based at least in part on: a frequency with which the selected instance of contact information was used for previous contact between the plurality of second users and the first user; and the selected instance of contact information corresponding to contact information used by a subset of the plurality of second users each of whom has a high affinity coefficient calculated with respect to the first user, wherein each of the affinity coefficients is calculated from information contained in the social graph, wherein each of the affinity coefficients represents the strength of an edge between the first node and a second node representing a respective one of the second users in the subset; updating contact information for the first user to specify default contact information in each category of the plurality of categories, wherein the default contact information in each category of the plurality of categories is the selected one of the plurality of instances of contact information; and providing, to each of a plurality of second computing devices corresponding to respective ones of the plurality of second users, the default contact information selected for each of the categories of contact information. receiving, for a first user of a social-networking system, from a plurality of contact-information sources, a plurality of instances of contact information, each corresponding to one of a plurality of categories of contact information; automatically selecting one of the plurality of instances of contact information in each of the categories of contact information as default contact information of the first user for use by a plurality of second users connected in a social graph to the first user, wherein the social graph comprises a plurality of nodes and a plurality of edges connecting the nodes, wherein a first node of the plurality of nodes corresponds to the first user, and a plurality of second nodes of the plurality of nodes each corresponds to a respective one of the plurality of second users, wherein: characterized in that the default contact information is selected based at least in part on: a frequency with which the selected instance of contact information was used for previous contact between the plurality of second users and the first user; and the selected instance of contact information corresponding to contact information used by a subset of the plurality of second users each of whom has a high affinity coefficient calculated with respect to the first user, wherein each of the affinity coefficients is calculated from information contained in the social graph, wherein each of the affinity coefficients represents the strength of an edge between the first node and a second node representing a respective one of the second users in the subset; updating contact information for the first user to specify default contact information in each category of the plurality of categories, wherein the default contact information in each category of the plurality of categories is the selected one of the plurality of instances of contact information; and providing, to each of a plurality of second computing devices corresponding to respective ones of the plurality of second users, the default contact information selected for each of the categories of contact information. a frequency with which the selected instance of contact information was used for previous contact between the plurality of second users and the first user; and the selected instance of contact information corresponding to contact information used by a subset of the plurality of second users each of whom has a high affinity coefficient calculated with respect to the first user, wherein each of the affinity coefficients is calculated from information contained in the social graph, wherein each of the affinity coefficients represents the strength of an edge between the first node and a second node representing a respective one of the second users in the subset; updating contact information for the first user to specify default contact information in each category of the plurality of categories, wherein the default contact information in each category of the plurality of categories is the selected one of the plurality of instances of contact information; and providing, to each of a plurality of second computing devices corresponding to respective ones of the plurality of second users, the default contact information selected for each of the categories of contact information.