robisto Only in a few places do the readings match the actual street signs.
Poland doesn't have much data in OpenStreetMap. OpenStreetMap is driven by volunteers, non-profit organizations, some companies and governments. None of them is very active in Poland.
Currently I am also working (low priority) on sqlite databases (from geofabrik.de) to do simply a lookup in a local database: Is a database available for a country -> do a lookup, otherwise do an internet call. This is also how navigation apps with offline maps do it.
GPS usage stays the same for location off course.
I already created some databases only containing "car" roads (so no bicylcle lanes etcetera) with speed limits (so not all car roads) and did some first tests.
I can't show data if there is no data, like @Gsibaja already mentions. The offline database shows already that Poland data is limited.
And another comparison for the countries, size, population and speed limit DB size.
| Country | Area vs NL | Population (millions) | speed limit DB (MB) |
|------------------|------------|-----------------------|----------------------|
| Netherlands | 1x | ~18 | 60 |
| Poland | ~7.5x | ~37–38 | 20 |
| Germany | ~8.5x | ~84 | 173 |
| United Kingdom | ~5.8x | ~67 | 82 |
| France | ~13x | ~68 | 93 |
| Italy | ~7.2x | ~59 | 36 |
| Spain | ~12x | ~48 | 30 |
| Ukraine | ~14.4x | ~36-37 | 7.2 |
Netherlands has a very active community. I was one of the volunteers for many years especially on houses and addresses (~100% coverage). The state company responsible for the roads shares their data with the Dutch volunteers group responsible for roads (we have multiple volunteer groups in the Netherlands). So yes: NL has > 90% coverage.
(And I can imagine Ukraine has totally different matters to worry about)
Finally: I can't tell you when this offline database functionality will be built in, if ever. It would not improve anything for Poland, or other "empty" countries, if there is no data added to it.
And I will not maintain all countries in the world. After all: internet usage is minimal.
(Edit: I create these databases with a python commandline script or an equal graphical UI script that extracts the country Db from geofabrik, extracts the road and speed limit data (if available), and builds the Db. If this functionality will ever be brought life, I will share the scripts so that everyone can build his/her country Db.)
