Some might suggest you download an app to convert a picture to a PDF on the iPhone, but the truth is you can do it for free without any apps.

How can I convert an image to PDF? Windows and macOS already offer integrated on-board tools with which you can convert images to PDF without installing additional software.

You can turn images into PDFs by clicking JPG to PDF, and pointing the website towards a file on your computer, in Google Drive or in Dropbox—choose your page size and margin options, then click ...