I bought an iPad recently and I've open PDF files using Safari and then a do open whit Adobe. now i can't delet the files. when i go to iTunes to delet or put files in Adobe they are there but in a file "inbox" and i can't open or delet that file. And the aplication on ipad doesn't allow me to delet any file, only on iTunes. Sorry for bad speeling

The Adobe Reader app for the iPad?

You can delete from it, though it doesn't appear so at first. The default view shows a Documents line, then a list of recent files. You can't delete anything here.

Tap the Documents. You'll now see all PDF's stored in the app. Swipe across the PDF you want to delete (as if you were lining it out) and a Delete button will appear. Tap it to delete.

I'd give you some screen shots, but I decided the app was redundant and deleted it a couple days ago.