We’ve written about the gTar in the past: a gadgety guitar that teaches people to play various songs with the help of LED lights and a smartphone app. Now the startup behind it, Incident, has signed licensing deals with Sony/ATV and EMI Music Publishing to add their catalogues of songs into its digital store. Players will be able to pay $0.99 for the individual track files via in-app purchase, and the licensing deal is a global one according to TechCrunch, so the store will be rolling out across the world with compositions by the likes of the Rolling Stones, David Bowie and the Beatles. gTar itself is still a bit of a niche product, given that it costs $399 plus shipping. But it’s part of a wider buzz around music-learning instruments and companion apps, which has plenty of potential for publishers.