Spotify readies iPhone app for its streaming music service

On-demand music streaming company Spotify is readying an iPhone client for its service, and expects to release it in a matter of weeks.

The iPhone software should be available as a free download from Apple's iPhone App Store in a few weeks' time, but using it to stream music will require a Spotify Premium subscription, the company's communications manager Jim Butcher said Monday.

Users of Spotify's desktop client software for Windows or Mac OS X can choose between the Spotify Premium music-streaming service costing €9.99 (US$14) a month, or a free service supported by advertising. Paid subscribers can access higher quality music streams, download music while travelling outside their home country, and hear new albums before they are available to users of the free service.

Spotify's service streams music at around 160K bps (kilobits per second) using the Ogg Vorbis q5 codec, and is available in Finland, France, Norway, Spain, Sweden and the U.K.

On the iPhone, it will compete with Apple's own iTunes Store, where users are charged to download tunes but pay no ongoing subscription fees. The iTunes Store contains around 10 million tracks encoded at 256K bps in AAC format, most unencumbered by DRM (digital rights management) restrictions, at prices ranging from $0.69 to $1.29.

For Spotify mobile users, there may be other charges on top of the Premium subscription fee: iPhone owners would be well-advised to choose a flat-rate mobile data subscription, or use the Spotify software only within range of free Wi-Fi hotspots, if they want to avoid high usage charges from their network operator.

To further limit such download charges, and to allow users to continue listening even when out of range of the wireless network, the Spotify iPhone client includes an offline mode that stores music files on the device for later playback.

Spotify published a video demonstration of its iPhone software on YouTube Friday, showcasing the offline listening mode and the instantaneous sharing of playlists between PC and mobile clients.

After the iPhone client is released, the company plans to release Spotify clients for other mobile devices, Butcher said, although he did not say for which platforms. The company demonstrated a prototype client for Android phones, also featuring the offline listening mode, at the Google I/O developer conference in May.