How to convert Apple's HEIC files to PDF on a Windows or Mac computer

You can convert Apple's HEIC files to PDF on a Mac or Windows computer using the free Convertio website.
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How to Reduce PDF File Size on Mac: 3 Easy Ways

Use Preview: Open the PDF in Preview, click File > Export, select “Reduce File Size” under Quartz Filter, and save. Use ColorSync Utility: Open the PDF in ColorSync Utility, click File > Export, ...

How to digitally sign a PDF when you don't have access to a printer and scanner

You can digitally sign a PDF in several different ways, including Adobe Acrobat, Apple's Preview app, and mobile apps, among other options.