Comment by pbmonster
10 months ago
> Would be nice if it were easy to share (offline) map data between apps. Download in app A, backup on sd card , use from app B, C, D, or on other device by swap/copy sd card. Maybe it's possible, but I haven't figured out how (on Android).
I'm also really hoping for that. Some kind of local OSM map server that all apps in the ecosystem call to provide geodata.
I run OSMand, StreetComplete, Organic Maps and Magic Earth on my phone. I need all of them to download the exact same geo data. And for convenience reasons, I usually load entire countries. It's so annoying having to download a country in app #3...
I agree, the issue is that the map data is highly customized. I believe StreetComplete uses online map tiles so that's less of a concern, but i.e. with Organic Maps the map data is highly tied to the app version: support for a data entry needs both app/rendering/logic support and presence in the data structure, and full forwards/backwards compatibility isn't always possible. The map files also need to be optimized for Organic Maps' speed/usability improvements over apps like OsmAnd: pre-indexing, etc. Maybe someday there's one standard format for it, but for now each app makes its own map files.
Also, mobile apps often have strict privacy lately around what files they can access: they're not just sitting on the filesystem, they're in access-controlled app-specific folders. That's good for privacy/security, but a dealbreaker for first-class sharing of information between apps.