With Sony Music finally signing the deal for Apple's music streaming service, reports are now saying that Apple iRadio is already set to conquer the market later this year. And its service will be free to users.

Sony Music is the last of the three giant music labels to get on board for the forthcoming radio streaming service from Apple, which is unofficially named as 'iRadio.' Universal Music signed its agreement with the iPhone maker in April..

According to reports, Apple and Sony were having difficulties reaching a common ground for the compensation of songs that will be skipped by users. But this latest development from Sony was reportedly pushed hard by Apple, so it will perfectly be in time for its announcement during the Worldwide Developers Conference (WWDC) organized by the giant tech company, set for Monday, June 10.

According to sources, the Apple iRadio music service will be free of charge to users, as its revenue stream will come from advertising units that will be handled by the iAd program of the company. This is different from other rival music services from Google Inc. and Spotify that require consumers to pay a flat rate fee before they can listen to the music stream. For instance, Google allows its user to have unlimited access to its music services for a subscription fee of $9.99 every month.

On the other hand, the Apple iRadio is projected to be similar with the service provided by Pandora Music, which acquires its income mainly fromadvertisers. However, because of the increasing expenses in music licensing, Pandora only streams music free to users for 40 hours. When users go beyond the time limit, they will have to pay for a subscription fee of $3.99.

The ad-supported Apple iRadio service will most probably be released with the iOS 7 launching slated for the latter part of 2013. Apple has not made any official statements about these details yet, but for sure, fans and enthusiasts will hear about it during the WWDC event.