To no-one’s great surprise, Google has launched a subscription streaming music service, Google Play Music All Access at its I/O developer conference in San Francisco.

It enables users to create a radio station from any song or artist they like, browse recommendations from Google, or explore by genre. Users can also add up to 20,000 of their own songs, which are stored for free in the cloud. The service costs  $9.99 (£6.50) a month ($7.99 a month before 30 June), with a free month’s trial. There is, however, no free, ad-supported version and no details as yet of pricing and availability outside the US.

Google also revealed at the conference that there have been 900m activations of the Android OS, and that the Google Play app store has seen more than 48bn downloads. It also unveiled a cross-platform messaging app, Google Hangouts, which allows Android users to chat via text or video, and exchange texts and images, with other Android, as well as iOS, users.

Finally, Google revealed that from next month, it will sell its own, unlocked variant of the Samsung Galaxy S4 on Google Play, running Android, but without Samsung’s own TouchWiz user interface. It will be available from 26 June in the US, with no contract, for $649, supporting both T-Mobile and AT&T, with LTE.

Stay tuned over the next couple of days for more news from the Google I/O event.