Sort of feel i've missed it in the instructions, as feel there must be a way to delete what you record; yet not found it yet, so presume its not implemented yet...
So can you please add a way to delete your tracks encase of mistakes, etc? 
Add a Way to Delete Tracks
I've deleted replies not pertaining to LoopStack, it's not often we get questions on other apps than Caustic so it's common for people to submit fixes that don't apply to LoopStack.
Anyway, to delete a track, you either record over it (pressing rec will stop it from playing until the loop rolls around) or set the undesired track's volume to 0 and drag another track on top of it. (you can always drag back afterwards)
Ha ha! The stupid thing is that I read this post the other day and realised it was about Loopstack yet my response today referred to Caustic. Oh dear, the old brain cells are dying fast...!