US application 20110230178, Jones; Gregory G.; (Seattle, WA) ; Hanson; Lisa M.; (Issaquah, WA) ; Kleist; Thomas; (Redbourn, GB); Hanson; Lisa M & Kleist; Thomas, "Mobile Communication Device Having Multiple, Interchangeable Second Devices", published 2011-09-22, issued YYYY-MM-DD, assigned to Microsoft Corporation