A computer-implemented method comprising: generating, by a computer system, a group of telephone contacts for a first user, wherein the generating comprises: receiving, by the computer system, a request to generate a list of telephone contacts for a first user; retrieving, by the computer system, email data associated with the first user; analyzing, by the computer system, the email data and identifying, by the computer system, a second user as a contact of the first user based upon a determination, based upon the retrieved email data, that the second user has at least a threshold email-based association with the first user; and adding, by the computer system, the identified second user to the group of telephone contacts for the first user, wherein a telephone contact entry for the second user in the group of telephone contacts includes a unique identifier other than a telephone number for the second user; receiving, at the computer system, a first request to connect a first telephone device associated with the first user to a second telephone device associated with the second user including the unique identifier other than a telephone number for the second user; identifying, by the computer system, a telephone number of the second telephone device using the generated group of telephone contacts for the first user; and initiating, by the computer system, a connection between the first telephone device and the second telephone device using the identified telephone number. generating, by a computer system, a group of telephone contacts for a first user, wherein the generating comprises: receiving, by the computer system, a request to generate a list of telephone contacts for a first user; retrieving, by the computer system, email data associated with the first user; analyzing, by the computer system, the email data and identifying, by the computer system, a second user as a contact of the first user based upon a determination, based upon the retrieved email data, that the second user has at least a threshold email-based association with the first user; and adding, by the computer system, the identified second user to the group of telephone contacts for the first user, wherein a telephone contact entry for the second user in the group of telephone contacts includes a unique identifier other than a telephone number for the second user; receiving, by the computer system, a request to generate a list of telephone contacts for a first user; retrieving, by the computer system, email data associated with the first user; analyzing, by the computer system, the email data and identifying, by the computer system, a second user as a contact of the first user based upon a determination, based upon the retrieved email data, that the second user has at least a threshold email-based association with the first user; and adding, by the computer system, the identified second user to the group of telephone contacts for the first user, wherein a telephone contact entry for the second user in the group of telephone contacts includes a unique identifier other than a telephone number for the second user; receiving, at the computer system, a first request to connect a first telephone device associated with the first user to a second telephone device associated with the second user including the unique identifier other than a telephone number for the second user; identifying, by the computer system, a telephone number of the second telephone device using the generated group of telephone contacts for the first user; and initiating, by the computer system, a connection between the first telephone device and the second telephone device using the identified telephone number.