MOG,Rdio Enters The Mobile Music

Two more companies are jumping into the mobile streaming music field with applications that work on iPhones, giving consumers new ways to listen to millions of tracks on the go for about $10 a month.

Music blog site MOG and a startup called Rdio, backed by Skype co-founders Niklas Zennstrom and Janus Friis, are both entering a market already served by Rhapsody International Inc. and Thumbplay Inc.

These so-called “cloud music” services do away with the need to download songs because the mobile devices tap into songs stored on distant computers through the cellphone network. In that way, they are the latest to challenge Apple Inc.’s grip on selling music as downloads through its iTunes store.

On Monday, a different startup called mSpot also launched to the public as a “beta” test, giving users a way to store music they already have and stream it to themselves on mobile devices. It’s free for 2 gigabytes of music, or about 1,600 songs; monthly fees are charged beyond that.

Along with access to 7.5 million tracks, MOG touts a slider control that gradually changes how many randomly selected tracks come from a single artist or many similar ones.