GridMaps Grid Editor for Umbraco
GridMaps is a simple grid editor for Google Maps that allows content editors to visualize Google Maps in the grid.
Release Downloads
NuGet Package: 
Installation
Install the package and add the Google Maps script to your master layout.
<script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initializeMap" async defer></script>
Settings
Remember to update the settings in ~/app_plugins/GridMaps/package.manifest"
You will need to set the defaultApiKey to a Google Maps API Key. Google - Get API Key