What development tool can I use to create a form field for pdfstamper?
What is pdfstamper? It's not an Adobe tool, at least not one I've heard of, so you may want to ask your question in a more appropriate forum. As far as form editing in general goes, you can create form fields in PDF files with Adobe Acrobat Pro and Standard.
I try to use Adobe Acrobat Pro (trial version) to create form fields. Adobe Acrobat Pro said that I need Lifecycle design. Where can I find lifecycle design?
You must buy and install LiveCycle Designer.
You only need that to edit certain old forms. You do not need it to make new ones.
Is this the iText class pdfstamper?