DJ Kit is a DJing application for Macs with lots of samples and instruments to choose from.
Included in the long list of available instruments are Bass Lines, Cymbals, DJ Effects, Drum Loops, Electric Keys, Hi Hats, Kick Drums, Mandolins, Scratch FX, Sitar Loops, Snares and many many more. There are 401 audio buttons in total ranging from one-shots to transitions, vocalized effects & more.
You can loop individual or multiple audio files simultaneously, Play & Stop audio in one window and use up to 45 Keyboard shortcuts for windows, audio buttons, looping and stopping audio. More recently, DJ Kit has been updated to include a new remote feature which enables you to access it via your iPhone or iPad although you must download this separately.
The interface of DJ Kit isn't great however and it doesn't really compare to more accomplished, polished applications such as Virtual DJ. The number of samples is however impressive.
DJ Kit is a comprehensive Djing solution although needs a lot of work on the interface.