Thumbplay has launched a full-track music store for mobile phones with a catalog of 1.5 million songs. With DRM-free tracks from Universal, EMI, The Orchard (NSDQ: ORCD) and INgrooves, Thumbplay is hoping to grab as much interest for full songs as it has with ringtones. As ringtone sales continue to slide, content companies are working with record labels to help shift that business to full-track downloads, but the takeoff hasn’t gone smoothly. Thumbplay’s DRM-free songs will cost 99 cents and can be downloaded over-the-air to more than 2,000 compatible mobile phones. The company said its hopes to expand the catalog soon to include Sony (NYSE: SNE), Warner and more independent labels. Thumbplay is also allowing users to transfer songs to PCs and portable music players like the iPod. Release.