iText 2

If someone uses the iText library in an android application for PDF without purchasing license, how will iText know he did that? Since he will not be releasing the source code how will they know he used their library? how could they take legal action against him? Again I am not planning in doing this. I was just curious.
I'm trying to create a java based plugin for an IDE (non eclipse), for which I need PDF generation. I started using iText, but I read somewhere that I cannot bundle this as part of my plug-in for distribution. I'm finding it hard to comprehend license agreements.
What is the difference between lowagie and iText. Is this just version difference or up-gradation to library. Which one recommended to be used.
Are iText Java libraries to generate PDF documents free, or do we have to pay for them?
Although the author has removed his Tweet, I once received the following notification from Twitter: Twitter insult This isn't really a legal question, because there is freedom of speech, but sometimes I regret that I even bother to look at new questions
Can iText 2.1.7 (MPL/GPL) licence be used in commercial projects? I am not a legal guy but lots of discussion threads suggest that there is no issue using the earlier version (2.1.7) of iText in commercial projects as that version is bounded with terms & conditions governed by MPL /GPL license.