The MultiDAW APP is pretty cool. I like the graphics of the Amplitude recorder though. There is also an APP that will hook all your recording APPs together, Audiobus. Guitartone is pretty cool and there is an Epiphone Eon APP that is good for looking up chords, if you need to. There is a Shortcuts for Cakewalk Sonar APP too, handy to open if you need it without opening anything else on the DAW.
I haven't looked for new APPs in a while. I don't have an iPad (yet) and my iPhone is only 16G. I live in a town where everyone you see is either going to or coming from a yard sale and the store (AT&T) looked at me like I was from another planet when I asked about a 64G iPhone, all they had were 16G phones. The WalMart here sells iPads and the biggest they stock is 16G. Amazing.
In September I am going to get an iPhone 6 Plus C. It is coming out with the newer 9 chip and more RAM (or whatever they call it, RAM I guess, supposed to be 2Gigs) I'm getting the 128GB model and be done with it.