Apple is working with the four largest record labels to stimulate digital sales of albums by bundling a new interactive booklet, sleeve notes and other interactive features with music downloads, in a move it hopes will change buying trends on its online iTunes store.

The talks come as Apple is separately racing to offer a portable, full-featured, tablet-sized computer in time for the Christmas shopping season, in what the entertainment industry hopes will be a new revolution. The device could be launched alongside the new content deals, including those aimed at stimulating sales of CD-length music, according to people briefed on the project.