Microsoft announced this evening its new music service, called “Xbox Music”, that aims to compete with iTunes, Spotify and RDIO. The service is set to launch tomorrow for the Xbox 360 and Oct. 26 for Windows 8 (coming pre-installed) and Windows Phone 8 devices. The service will also launch as an iOS app shortly after, GigaOm noted:

But the biggest story to me is that Xbox Music will embrace Android and iOS. Jerry Johnson, general manager of Xbox Music, wasn’t able to tell me exactly when the apps for those two platforms are going to come out, but the sense that I took away from the briefing was that his team is working on making it happen sooner rather than later. Xbox Music on Android and iOS will look very much like Xbox Music on Windows Phone 8, which itself in many ways follows the style formerly known as Metro.

Microsoft’s service will be for limited hours of free streaming after six months, so Spotify might not need to worry just yet.

There is no word on what pricing iOS users will see, but Microsoft said it will offer a free ad-support version for Windows 8 device owners and a $10 ad-free plan for those wanting an ad-free experience.

More details are at TechCrunch.