I like to record loops through the sound mixer to the iPad into Loopy. I will connect mic and music instruments into the sound mixer.
Anyone can tell me what hardware I need
Connect your instrument to one of the recomended interfaces (see below). Connect the interface to the iPad via the USB connector in the Apple Camera Connection Kit (CCK).*
If your interface has multiple inputs, you can select which input to use from the sidebar in Loopy.
*Note:
The CCK is not compatible with iPhone or iPod Touch.
If you have an iPad with a lightning dock connector, you will also need to buy an adapter from Apple to use the CCK. it is recommended that you use the 30-pin to lightning adapter cable rather than the adapter block.
The lightning CCK also works. (http://store.apple.com/us/product/MD821ZM/A/lightning-to-usb-camera-adapter?fnode=3a)
Comments
There are details on the wiki page. http://wiki.loopyapp.com/