Amazon's Prime Music service is celebrating its first year in the US, claiming to now have several million Prime members.

The streaming service launched in June last year, with hundreds of playlists and more than 1 million songs in its catalogue - although it launched without having reached a deal with Universal.

Now, Amazon claims it has more than 1,000 playlists, while playback hours have tripled since September 2014. Membership has also more than doubled in the last nine ...