Hoping to capitalize on the media frenzy surrounding the Federal Communications Commission's investigation into the iTunes app store approval policies, RealNetworks announced that it had submitted a Rhapsody iPhone app to Apple for review.

The Rhapsody app has not yet been approved, but one of its principal competitors in the subscription music space, Napster today discussed the difficulty of bringing a streaming music app to the iPhone, as it unveiled the beta of a new mobile Web interface at m.napster.com where its subscribers can browse, search, preview and buy songs, but not stream them.

"One of the most common questions Napster receives is, 'When will you offer an iPhone app?' Well, Napster has created an iPhone application that allows subscribers to stream music on-demand to their iPhone??"including personal playlists, albums and radio stations. You can imagine the company is also looking at streaming applications for several other mobile platforms as well (Blackberry, Android). However, due to the high licensing fees for streaming to a mobile phone, Napster has not yet submitted the iPhone app to Apple for approval or attempted to bring the application to market."

"iPhone users can use m.napster.com and song credits to purchase songs, but the songs purchased are sent to the PC only, as Apple does not allow 3rd parties to download songs 'over the air' to the iPhone," the company said today.