1. A method comprising: responsive to a presence status change of a first client application of a first client device, the first client device providing presence information of the first client application for a first account to an external presence server via an API of the presence server; the first client device providing a first presence request to the presence server via the API, the first presence request being a request for presence information for a first contact list of a plurality of accounts specified by the first presence request; the first client device receiving the presence information for the first contact list from the presence server via the API; the first client device processing the presence information of the first presence request by using the first client application; the first client device providing a second presence request to the presence server via the API, the second presence request being a request for presence information for the first contact list; the first client device receiving the presence information of the second presence request from the presence server via the API; the first client device processing the presence information of the second presence request by using a second client application of the first client device; and responsive to a presence status change of a third client application of a second client device of a second account, the second client device providing presence information of the third client application for the second account to the presence server via the API of the presence server.