When it comes to music, YouTube is said to be making a big move that might have Spotify looking over its shoulder.

Six million customers pay Spotify $10 each month to listen to any song in its library, commercial free, at home or on a smartphone. Now YouTube wants in on the on-demand action. The Google-owned video streaming service is said to be working on its own on-demand music platform that could compete with Spotify head to head.

The service, as Billboard reports, will likely let mobile users stream an unlimited number of songs, on-demand, for free. A premium paid service could offer users unlimited access to Google's subscription All Access music service, ad removal and an offline mode.

Spotify, in comparison, charges users $5 to listen to artist- or track-based radio stations commercial free. On demand access and offline mode costs $10.

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YouTube's main objective, however, is to attract more users to advertise to. YouTube would remove the ads if you pay them, but that's the revenue they're really after. In contrast, Spotify hopes users will pay them to get rid of pesky ads, which interrupt free users after every 15 or so minutes of music play.

When contacted, YouTube declined to comment about its plans for a new music service.

"We're always working on new and better ways for people to enjoy YouTube content across all screens, and on giving partners more opportunities to reach their fans," a spokesperson said. "However, we have nothing to announce at this time."

For years, high school and college students have been using YouTube in just this way: streaming official and unofficial uploads of their favorite songs instead of downloading them from someplace like iTunes or even illegally. YouTube's new plan could make it easier to use the service in a manner people already enjoy.

Last month, YouTube announced plans to let users temporarily download video clips to be watched offline later. Both features could potentially give artists more exposure and revenue since fans will be able to enjoy their content more frequently and in more places such as airplanes and subways.

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