Indeed, OsmAnd works wonders offline on phones: there's a ton of detail compared to some proprietary services, at least in some cities, and routing works fine w

Indeed, OsmAnd works wonders offline on phones: there's a ton of detail compared to some proprietary services, at least in some cities, and routing works fine without internet connection (with the exception of public transport when the data is not in OSM). It's not entirely free, namely map updates are limited without a subscription—though I haven't checked if it's the same with the F-Droid version.