Hands on with the Spotify iPhone app

It is one of the most hotly anticipated apps yet to appear on the iPhone.

From today, Spotify – the digital music application credited by some for finally luring listeners away from online piracy – can sit alongside iTunes on Apple’s mobile, as well as on phones running Google’s Android software.

On the PC, Spotify allows its users to listen to any of its millions of tracks for free, supported by advertising. On a mobile, users must upgrade to its premium subscription, which costs £9.99 a month or £119.88 a year (and also provides ad-free listening on the PC).

The achievement in bringing Spotify to the mobile is not just technical. It has negotiated wireless rights to its entire library (no mean feat) and even allows users to store some songs for “offline” listening, in spite of fears that Apple would prevent it from doing so for fear of competition with iTunes. For Spotify, the mobile app is a crucial tool in selling subscriptions to its millions of free users.

I’ve been playing with the Spotify application on my 3G iPhone after downloading it from the App Store this morning and in general the experience has been good – but perhaps not a complete replacement for iTunes.

Connected to the O2 3G network in central London, the first song I searched for was an early B-side from Britpop band Suede (just to stretch the catalogue a bit). Finding the song was simple – you can search by track, album or artist – and you simply tap the title to start it playing. In a nice touch, more results automatically load as you scroll down the list.

After a brief moment, the song started playing, paused 5 seconds in, then played for another 24 seconds before another little break. After that the track played judder-free for the remaining minutes. The music plays at roughly the same bitrate (a measure of sound quality) as the standard desktop player, around 160 kbps, although premium subscribers get up to 320 kbps on the PC. On my home wifi network, which runs at around 6 mbps, the experience was smoother.

Listening to tracks offline – in an aeroplane, for instance, or on the London Underground – is one of the features that makes Spotify stand out over other music apps. But this requires a little preparation before departure. First you set up a playlist or two, which is possible on the iPhone itself but easier on Spotify’s desktop software. Because you use the same login details, these then automatically appear on the mobile version. You can “cache” a maximum of 3,333 tracks on the phone, if its memory can take that many.

Downloading them to the iPhone requires a wifi connection. It took me about 5 minutes to sync two dozen tracks, so a whole flight’s worth would take some advance planning.

Caching works to a limited extent when out of wifi range. As I was descending the escalator down underground to the Tube platform, Blur kept playing in my headphones for a short while after my mobile connection had disappeared. After it cut out, I was able to rewind to the beginning of the song and listen to most of it again.

Out of habit while on the Tube, I closed the Spotify app to read emails on the iPhone – and the music stopped. With the iPhone’s own player, the music would keep playing but the device doesn’t allow other applications to keep playing in the background. Spotify at least helps to ease the frustration of this by picking up where I left off when I reopen the app.

Back above ground, the search bar becomes green to indicate that the mobile network is available (although I couldn’t search again without restarting the app). The 3G experience has been pretty faultless after that early wobble. However, listening via O2’s 2.5G Edge network was not so successful, with juddering every few seconds, which could be a problem for those outside urban areas.

The Spotify app’s biggest limitation could be its impact on battery life. Just a couple of hours’ listening this morning used up a third of my iPhone’s charge, although most of that was over-the-air streaming; cached music would presumably be less power-hungry.

Some users have complained on Twitter that the app intermittently closes itself, but that hasn’t dented enthusiasm for the service, which is among the most-discussed topics on the micro-blogging service.

On Twitter, Spotify’s product chief said that a BlackBerry app is on its to-do list and other mobile platforms will follow, including Symbian S60, which could see it competing with Nokia’s Comes with Music service too.

On first impressions, Spotify is a worthy addition to the mobile-toting music fan’s toolkit. Whether it can help justify Spotify’s $250m valuation, however, is another matter.