For whoever happens to be experiencing problems with it:
Magic Earth was slow and often crashed on startup. I found out that and the cause was in the SD card. After removing it, I no longer have any problem.
For offline usage I had previously switched from sd card storage, (configured as external storage), to internal phone storage and again later decided to use Magic Earth online only. But the app continued to have problems while the sd card was in the phone (unused / empty).
Now I am still going to test if it is just this particular sd card or if another card does work.
But in the meantime, I can live with the fact that I only use Magic Earth’s online mode. For offline navigation, I use Organic Maps. That works very well.
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