What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
How about using the PDF Previews Widget
You can check it here http://widgets.jotform.com/widget/pdf_previews
This PDF widget allows uploading of PDF file into the jotform and after uploading, it provides a preview window and selection option.
You can test this demo jotform http://form.myjotform.com/form/41242004590543 . Upload multiple PDF file within the jotform and do a preview/selection before finalizing the selection by submitting the form.
Hope this help. Inform us if there is more we can help you with.