Slacker is an interactive Internet radio service, available in the US and Canada only. Listeners can access the service on the web, through mobile apps on multiple smartphones as well as on the Slacker Personal Radio Players and other devices. It allows users to create and share customized music stations starting with either Slacker's presets or a list of artists. In April 2009, the service had over 2.4 million songs, organized into over 100 programmed stations and 10,000 artist stations.