To show an ad, which is eligible to appear on search partner sites, on the mobile version of Google Maps, you should use:
- product extensions
- location extensions
- mobile extensions
- store visit extensions
If you opt to advertise with Google search partners in your campaign network settings, your ads with location extensions can appear on partner sites. Ads with location extensions on these sites can vary in format, and they might show a map.
Read more here: https://support.google.com/adwords/answer/2404182