No matter what kind of beats you're making, I strongly recommend DCAM.
Video tutorial and online review for iSequence, one of the best the apps that let you make songs right on your iPad.
Check out my DubSpot review of Propellerheads' software that changed the world: ReBirth-338 for iPhone.
iPad app reviews: TouchOSC is control for your computer. Sonorasaurus a horrible DJ app which shows us that although the iPad is great, it is not ready for native DJing yet.
iElectribe and Looptastic HD are two of my favorite music apps for the iPad because of their sound quality, ease-of-use, and features.
TC-Helicon’s Harmony4 is a must-have plug-in for any producer working with the TC Electronic PowerCore
Ableton Live is one of the most unique and widely used sequencers on the market today.
Logic has been in the scene for a long, long time. If you’re reading this, then you’ve heard of it already. It’s no secret or mistake that Logic is as popular as it is. Read this older review of Logic Pro 7 at MusicPlayers.com.
Riding closely on the heels of their first hardware release (Rig Kontrol for Guitar Rig), KORE is a hardware/software combination that functions as a standalone software host for running plug-ins.