Yes, it is a well-built app and it is simply gorgeous to work on and modify your PDF docs.
The problem? A HUGE one: the app cannot manage files bigger than 25-28 MBs (a quite small size indeed if you have to work on either a "big" file or some little ones). On the description it is not said, but the app makes the whole iPad suddenly reboot. Once you re-launch the app, everything you didnt save before the sudden reboot is lost. I emailed the support asking for a bug fix so that the app could be usable again, they answered that they were fixing the issue and that a bug fixing upgrade should have been released in a couple of days. It was august.
I re-emailed them and they havent responded. Good boys
Dockmock94 about TinyPDF - Fill Forms, Annotate PDF with Professional Reader, v3.3