If you wanted to do some virtual mixing of songs from your iTunes library directly on your iDevice, you had to use the apps DJ for iPhone and DJ for iPad. Now there is Pacemaker, a new app for the iPad that gives you additional options. Although the turntables do not look quite as stylish as the ones of the DJ apps, Pacemaker interacts with Spotify songs.
This unique characteristic will definitely please all Spotify premium users. The basic version itself is free. However, if you would like to utilize all effects, which would make sense, you have to obtain a package to upgrade to the full version via in-app purchase. If you are not interested in the complete package right away, you have the option to add individual packages at a lower price.