Algoriddim has released djay 4.0, an update to its DJ app for the Mac. The new version introduces a Harmonic Match feature that enables “music enthusiasts to create the perfect mix.”

djay for Mac is a music app with a visual interface that enables music lovers to compose beats, DJ a party, create playlists and more. Version 4.0 is optimized for Mac OS X 10.7 (“Lion”).

With the introduction of the new visual key match wheel, djay automatically registers a song’s key and matches it to songs of the same key within an iTunes music library. This integration of harmonic mixing capabilities enables easy mashups that are pitch-perfect, says Karim Morsy, CEO of algoriddim.

djay 4.0 requires Mac OS X 10.5 or higher and costs US$19.99. It’s available worldwide exclusively through the Mac App Store in the Music category.