As of today, you can use HD maps in Gaia GPS for OpenLandscapeMap, OpenHikingMap, and OpenCycleMap.
These sources work great on retina and high resolution devices. The addition of HD maps answers a common request for the ability to increase text-size on higher resolution displays.
How to Add HD Maps
To add the new maps, open the “More Layers” menu. Find OpenHikingMap and OpenCycleMap under “Gaia Recommended” and OpenLandscapeMap under the “OpenStreetMap” heading.
Previously Shipped, Now Live
The last iOS and Android releases actually included HD map capabilities, but due to an issue with existing app installs, we had to wait a week to make the maps available. Check out the new maps today, and email firstname.lastname@example.org with any comments.