I only know of one that's in Germany, I've never been there personally but you select your mate and they prepare it for you, they're mostly focused on chimarrao afaik. But they seem pretty chill, so I don't think that there would be any issues if you brought your own cuia.
You could also just get the APK file from APK mirror. But after trying the official one (patched mind you) I uninstalled it, it's just too bad. If lemmy needed any advertisment, I'd say that the official Reddit app is doing a pretty good job at it.
Thanks, go for it, try it, there's nothing to lose. The only thing is, that the powdery type (chimarrao), can be difficult to prepare for a beginner. There might be yerba mate bars in your country, that would probably be the best way to experience it for the first time if you don't have any friends or family that drink it. Anyway, this one is called Jacutinga and it's fighting for my most favorite one against the meta mate from Gehm family.
I can confirm that this works. It's what I did and I'm a lot happier than when I worked a job with an average salary.