BuyFromEU

It's great and the most complete one in the Czech Republic and Slovakia but the Android app has been enshittified to only allow offline maps of one country at a time unless you pay a premium subscription. The rest of the world is "just" OSM but they use a great skin, especially for the tourist map.

While hiking in Romania, where the tourist trail marking 🇯🇵 is more like a suggestion, not like the Czech one, where you pretty much always see at least one sign from anywhere on the trail, they've been great. However, there is an inexcusible mistake I found in Bihor: you think you can take a 10-meter shortcut between these two points by walking over a few rocks with barely any slope?

In reality, you end up falling into a 70-meter gorge. The elevation data and contour was imported incorrectly and does not line up! I complained and they said they wouldn't fix it.