jPDFFields allows your application to get and set field values.
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PDF Joiner - This online tool allows you to join several PDF documents into a single file, free of charge.
iText - iText is an intuitive and refined text editor with word processing completely rewritten in Cocoa...
DocuPUB - DocuPUB is an online file converter, file merger, file compressor, and file resizing tool.
Post.As - A simple tool to publish _____ on the web
PDFill - Open, View, Edit, Save and Print PDF Documents without Adobe Acrobat