Your PDF files probably already have links to open web-sites and send emails, but what about adding an even more advanced layer of interactivity for the user? This script will take any telephone numbers that appear in your file and convert them into clickable links that will launch the Skype application (if installed, of course), and automatically bring the telephone number up so the user can immediately call it.

For example, let's take this bank's Contact Us page and run the script on it:

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The phone numbers on the page already have a country-code (+44), so we leave that option blank:

The script created 3 links:

We can see them by hovering with the mouse above one of them:

Clicking it immediately launches Skype and prompts us to call this number:

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The script even comes with an Action (if you have Acrobat Pro) that allows you to process multiple files easily.