PDF Reader provides 2 ways for you to add password protection to PDF files:
Encrypt PDF (to the current PDF)
1. Launch PDF Reader and switch to the "Documents" tab( ).
2. Tap the "Edit" button on the top right corner of the screen.
3. Select the file(s) and tap the "Encrypt" button
4. Enter a password and tap "OK" to encrypt the PDF with password protection .
6. The encrypted files will be saved in file list
Encrypt PDF (from within the app folder)
1. Launch PDF Reader
2. Switch to the “Home” tab and click on the “Encrypt PDFs” entrance
3. You can choose one or more files from the file list in PDF Reader
4. Then enter a password to encrypt the PDF(s)
5. The encrypted files will be saved in file list