The Maps Activity has some prerequisits before it can funtion properly.
Make sure to add this line into the local.properties file:
MAPS_API_KEY=AIzaSyAgT-T1wyMbPajwpTs_XodlI0T_4MQWuCE
You also need to add dependencies to the Google Maps SDKs - by clicking on the cube icon near the device manager > SDK Tools > all the google packages
When you click on a marker, in the lower right corner two buttons will pop up to take you to google maps, showing you dirrections, reviews, and everything else included in Google Maps.