Adwords announced yesterday a new feature on the Landing pages tab. On Landing Pages page, you will see which URLs in your “account are mobile-friendly, which ones drive the most sales, and which ones may require your attention. For example, find the pages that get a lot of clicks, but aren’t mobile-friendly. Then prioritize them for your webmaster so you can convert more of your ad clicks into sales.”
Basically, if the landings are not mobile friendly, the bounce rate and conversion rate will be worse.