What cards can you recommend for use in the application?

Question

Java

What are the cards, except from Yandex and Google, that you can add to your application?

Answer 1

Openstreetmap.org is the only free product for any application, there are no other options.
if you take tiles, then you need to put "(c) openstreemap" in the corner of the map,
plus there are a bunch of alternative to the main tile-renders
there are offline maps on the MapsForge library