Cloud-based music service Rdio today announced the availability of its Rdio app in Verizon Wireless's V CAST Apps store. Rdio will be available through V Cast and will take advantage of Verizon Wireless' direct billing, where apps purchased are invoiced on customers' monthly account billing statements.

Rdio's Unlimited service allows users to search and play any song, artist, album or playlist from its catalog of more than 8.5 million songs. Users can also listen to music when offline.

"Our new relationship with Verizon Wireless makes the Rdio social music experience available to millions of mobile subscribers and simple to pay for through direct carrier billing," said Drew Larner, CEO at Rdio.

Verizon Wireless customers who download Rdio can access a seven-day free trial, after which Rdio users can elect to subscribe to Rdio Unlimited for $9.99 per month.

Just yesterday, Rdio announced a partnership with Echo Nest, to help developers build music apps on a catalog of more than 8 million licensed songs while tapping a new source of revenue. The first of these applications, Music Maze, is a steerable music streaming service that traces similarities between millions of artists after the listener starts with a single suggestion.