Garmin’s Quickdraw Community lets boating anglers share HD mapping content and download user-enhanced data to supplement existing Garmin mapping options. The Quickdraw Community builds on the success of Quickdraw Contours, a tool that lets mariners using Garmin electronics create personalized HD maps with 1-foot contours on any body of water. Results are viewed in real time or created in the background for later use. To access the Quickdraw Community, users need to create an account through Garmin Connect.
It’s free, and you can find more information at the Garmin Quickdraw website.