Not too sure about this one.

iPhone 3G with ver 4Os.
The signature part seems to work ok, but crashes while trying to write text. It seems to have an unknown character limit where it just stops responding. The return button while adding text doesnt work.
Good idea, but needs some work. It would be nice to be able to select and cut text from a pdf file, even if just to paste a white square over it, and then replace with text input.
I have to say, Im a little choked with this app.

Tcs-Pendragon about Sign It! - Fill, Sign and Send PDF Documents