Navico, a marine electronics company which owns Lowrance, has announced a cartography toolkit for third-party map developers. The handheld Lowrance Endura series is among those supported, and the toolkit also supports raster imagery.
There’s no word on the cost of becoming a developer; hopefully it is less than Garmin’s $5,000+ fee. I requested a copy of the Navico license agreement, but haven’t heard back from them yet.
Here’s the full news release.