Spotify, the legal streaming music startup that has wowed even Mark Zuckerberg, has now had its iPhone app approved by Apple, and now awaits an appearance on the App Store. How did they get an app approved which streams thousands of music tracks on demand and which potentially competes with iTunes? The short answer is no-one is saying quite how, but it’s pretty easy to surmise that iTunes won’t be affected since the app will only work for paying Spotify subscribers (who currently pay a premium subscription which currently stands at €10 a month in Europe). In which case Apple’s policy of blocking apps that duplicate native apps (like iTunes) would not apply. The green light from Apple now leaves the way open for Spotify to launch in the US, as it’s been planning, and attempt a massive change in the music industry for the record labels that have invested in it. No mean feat.