Little guys have to stick together.

Sprint and Napster — two underdogs in their respective industries — announced a new agreement today to add Napster as a new music streaming option.

Sprint’s iOS and Android subscribers get one month of free access to Napster’s premium music service and then can sign up to have the $10 a month subscription charged through their wireless bills. Sprint customers will be able to stream Napster music without counting against their data plans.

Sprint adding Napster could help the Seattle-based company grow its audience. It currently has about 3.5 million subscribers to Spotify’s 40 million and access to Sprint’s customers could help broaden its reach. Sprint also allows customers to add Spotify to their monthly bills.

As part of the deal, Sprint also added Napster to its prepaid brands Boost Mobile and Virgin Mobile.

Napster also has a deal with Bellevue, Wash.-based T-Mobile. Under that arrangement, T-Mobile’s Simple Choice Plan subscribers get access to Napster’s radio app and certain plans can get Napster’s premium service at a discount.

Napster also announced other partnerships Thursday, including an agreement to add its service to German airline Lufthansa.

In addition to the partnerships, Napster is throwing its weight behind the Open Music Initiative, a non-profit launched by the Berklee College of Music that aims to apply open-source standards to the music industry and ensure that artists are fairly compensated.

“Our global partnerships not only expand all the ways people can access and listen to music around the world but also set the foundation for Napster’s long-term growth and a sustainable music industry,” Napster CEO Mike Davis said in an announcement.

Editor’s note: This post was updated to clarify the relationship between Sprint and Napster.