Native Instruments has released an iPhone version of Traktor DJ. I've spent a long time pouring over the two iTunes descriptions, and I believe the features in the iPhone version are identical to the iPad! Like its big brother, this requires iOS 6.
Traktor DJ for iPhone iTunes Description:
Revolutionary DJ app by Native Instruments – makers of the leading pro DJ software Touch the groove using familiar iPhone swipe and pinch gestures Direct access to your iTunes music library from TRAKTOR DJ Stylish waveform display allows for simple looping and ultra-tight scratching Ingenious use of iPhone’s compact screen real estate – instantly swipe from one-deck focus to split-screen view The most affordable way to get started with TRAKTOR pro DJ software to date Intelligent browser recommends songs based on compatible tempo and key Automatic tempo and key detection plus BPM sync for super-smooth mixing Innovative Notification Center gives you in-app access to essential tips and undiscovered techniques 8 built-in pro DJ effects including Reverb, Delay, and dramatic glitch effects like BeatMasher Familiar DJ mixer layout with crossfader, 3-band EQ, and filter on each channel Prepare tracks on the road – all meta data (tempo, beatgrids, cue points etc.) in TRAKTOR DJ syncs with TRAKTOR PRO DJ software using Dropbox Record your mixes live in high-quality on the iPhone and share with your friends