DETROIT, Mich. -

Technology giant Apple plans to reveal its brand new music streaming service, iRadio, at a developers conference this upcoming week, which will compete with other free music services Pandora and Spotify.

The completely ad-backed iRadio, which will launch later this year and will have ads sold by its iAd division, will be making selling big-brand campaigns to advertisers a key priority.

But already, concerns about the cost about Apple running such a service have been raised. Music service Pandora, with roughly 70 million active users, has had to give its users a 40 hour listening limit before asking for a $3.99 subscription. Competitor Spotify also recently placed a similar listening limit. Pandora's stocks have dropped 17% this week since the news of the news that Apple was close to announcing its new service was leaked.

It has also been rumored that, in light of hearing Apple's plans, Amazon and Google are also considering joining the free music streaming empire.

Although music streaming has not gained as much popularity as iTunes, it continues to be a growing market.

Apple, also a top producer of smartphones, has recently become the first company to offer users free trade-ins of old phone models for new phones, as its competitor, Samsung, steps up its game in the sales of Android phones and pushes ahead of Apple. A new model of Apple's iPhone is scheduled to be released soon.