I need to lock a 12-page PDF before I email it from my phone, and I can’t figure out where the password option is. Has anyone done this without a computer?
Honestly the easiest way is using the free Adobe Acrobat app. Open the file, tap the three dots menu, and there is a set password option right there. I have to do this with client contracts all the tiem.
Yes, it is possible, although the exact menu depends on the phone. I would open the PDF in Adobe Acrobat, choose “Protect with Password” from the three-dot menu, enter the password, and save a new copy. That feature may require a subscription; for an invoice, I would avoid uploading it to an unknown online service.