The doubleTwist application enables users to send photos and videos to their friends and sync their media library to a wide variety of portable devices.
It is compatible with iTunes and Windows Media Player, allowing users to sync movies, pictures, music, and playlists to their mobile device through USB.
An in-app purchase enables "pro" features including "AirSync" which allows sync over WiFi, AirPlay, UPnP/DLNA support, equalizer, album art search, and removal of podcast ads.
On Friday June 5, 2009, “The Cure for iPhone Envy” billboard ad[4] was put up on the BART exit outside the flagship San Francisco Apple Store.
[6] BART cited several advertising criteria violations as reasons for the ad being removed, including the original being too dark, and the subsequent redesign inappropriately having a white background.