How to make book save locally in PDF format?

I’d like people to able to save the flip book document as a PDF. How is this possible?

If you want readers to download your original PDF document and save locally, you can enable "Download" feature while converting with Flip programs. More details as below shows:

1. Start Flip program, import your PDF file and enter into design interface;
2. Set "Tool Bar Settings->Buttons Bar->Download setting", "Download Enable->Yes" and input PDF link as "Download URL", you can upload your PDF online and use web link, or just use relative path as "./files/download/yourfile.pdf", then put the PDF into the output folder "files/download" after outputting;
3. Output your book, or publish online(more details about uploading book online here).

Then when read your books, readers can click the "Download" button to save your book PDF copy locally.