Dropbox, or via WIFI or a USB flash drive, whatever you like, things changed a lot with files.app, iPad has a robust(ish) file system now. Beatmaker has a built in Dropbox browser, Nanostudio has built in network drive support, will see any computer as a drive. I have the 1tb dropbox, so i just use that and put teh samples direct on the iPad storage too. Recording samples you will need an interface of some kind, if you have a PT01 or something you can USB that straight in too.