Telephone Numbers on Smart Phones

To make a telephone number clickable on a smart phone you simply need to add a little HTML code.

Example:

<a href=tel:+15127365710>512-736-5710</a>

or

<a href=tel:+15127365710>Click to Call the Web Team!</a>

Note the syntax is similar to email addresses: <a href=”mailto:cofawebmaster@austin.utexas.edu”>cofawebmaster@austin.utexas.edu</a>
mailto: and tel: are both protocols.

Learn More

CSS Tricks goes into extensive detail in the article, The Current State of Telephone Links.