
The crowded Web music scene —
Apple on Monday launched iTunes Radio, a free streaming-music service for desktop and mobile devices. As more people grow comfortable with playing songs online instead of downloading them, the streaming-music landscape has grown crowded. Here's a look at some of the players.

Pandora —
With more than 150 million listeners, Pandora is the Web's most popular music-streaming service. Launched in 2005, it acts like a personalized Internet radio station, serving up a steady mix of free tunes based on users' recommendations. Paying users get an ad-free version.

Spotify —
Launched in Sweden, Spotify came to the U.S. in 2011 and has built a sizeable audience through its partnership with Facebook. Spotify caters to the instant-gratification crowd by letting users stream anything for free from its library of 18 million songs.

Xbox Music —
Microsoft launched Xbox Music in the fall of 2012. Like Spotify, it lets users instantly stream music -- to the Xbox home-entertainment system or to Windows-powered PCs, tablets and phones.

Google —
Among teens, YouTube already is the most popular way to listen to music, according to a Nielsen survey. A Google music service would reportedly let YouTube users subscribe to streaming-music options as well.

Twitter Music —
In April, Twitter signaled a music site is coming soon, going live with a webpage (albeit one that didn't yet do anything). Unconfirmed reports suggest a Twitter music service would suggest songs for users based on several criteria, including who they follow on Twitter. Ryan Seacrest has already sung its praises -- on Twitter.

Google Play Music All Access —
Google announced its own streaming service, Google Play Music All Access, in May. It combines the millions of songs in the Google library with users' own music collections, which can be uploaded to Google Play. The service works on the Web and on mobile devices.


