To serve the same basic purpose as my question about split-screen apps:
Is there an app that allows me to quickly (in one touch or zero!) bring up a notepad/text editor while I'm in another app?
This would be immensely useful for things like taking notes on a PDF that I'm viewing. . I realize that certain apps may include note taking functionality, but these do not suit the need for a universal way of taking notes, which TextEdit on my Mac does nicely.