In order to appeal to customers on mobile devices, it’s important to:
Send users to a video-based landing page
Send users to a mobile-friendly landing page
Avoid using ad extensions
include your phone number as your display URL
When creating a mobile website use strategies that make the most of the size of mobile screens and how people use their phones. These strategies can help make sure your mobile site offers a great experience for customers and helps them accomplish their goals on your site. In turn, this means better business for you
People seeing your ads on mobile are more likely to want to know where you are, or to call you. Show your location and phone number with location extensions and call extensions. Also, consider creating ads devoted to people on mobile devices, using the mobile version of your website as a landing page, and offering specials suited to a mobile audience. Keep in mind, your text ads can appear differently on mobile.
Read more here: https://support.google.com/adwords/answer/1704392?hl=en