Portland-based online music licensing firm Rumblefish has launched a new, mobile software development kit aimed at Apple iOS developers, the firm said today. The firm said its new mobile SDK makes it easier for Apple developers to recommend soundtracks to use with videos and photos inside iOS apps. In new software development kit allows developers to tap into Rumblefish's music catalog, which it says now has over 750,000 songs, and allow users to license tracks for use in those apps. In a related move, Rumblefish said it has also made a major update to Friendly Music, which provides licensed, pre-cleared soundtracks for people developing YouTube videos. Rumblefish is an online music licensing provider, which allows people to license music and tracks for their videos and other projects. The firm has been providing music tracks to the TV, film, advertising, and video game industry for years.