Well, now, the party's gonna bump a little harder: Algoriddim on Thursday announced that it's updating its popular djay 2 apps for iPhone and iPad to include integration with the Spotify Premium music-streaming service, giving pro DJs a deeper well of music to use in the club and adding features that will make amateur DJs seem a bit more polished.

The Spotify integration will give users access to 20 million tracks, though you'll need to be a subscriber to Spotify's $10-a-month premium service to use this feature of the app--despite the fact that Spotify is otherwise now free on iOS. The feature is able to access a user's Spotify playlists, starred tracks, and inbox, and it also offers ready access to songs at the top of the music charts. Djay users will be able to switch back and forth between Spotify and their own iTunes library "seamlessly," according to Algoriddim.

Other major upgrades include Match, a new feature that recommends tracks based on the song the DJ is currently playing, making for a more seamless listening and/or dancing experience. The feature is powered by The Echo Nest, recently purchased by Spotify, which selects the track "based on danceability, BPM, key, music style, and how well the song mixes with the currently playing track."

Users who want to let the app do the work can use its Automix Radio feature, a sort of "shuffle" mode that lets a user pick the first track, then picks and mixes successive tracks with beat-matched, DJ-style transitions.

The upgraded app also includes integration with DJ hardware from Pioneer, Numark, Vestax, Reloop, Philips, Casio, and Griffin; "social sharing" of set lists and music choices; and 30 new "desktop class" audio effects. (See this video for a demonstration of the upgraded app.)

The update is free to all existing users of djay 2. The iPhone version of djay 2 is usually $2, but is free during launch week. The iPad version--usually $10--will be half-price during the launch.