Should I write app reviews to Mac App Store in English or in my native language?
Solution 1:
App Store is divided by countries it is available in and each country's App Store is a separate entity. For an end-user (me, you, anyone who buys apps basically) there is no cross-over between them. If you're from Finland you're most likely using Finnish App Store (possibly with interface in English).
Only users of the same store will see the reviews posted in it. Reviews are not shared between individual (country) stores so it is perfectly fine for reviews to be in country's native language.
Solution 2:
I disagree with Joshua, but without hard feelings ;)
I'm an Italian living in the Netherlands. This gives me the Dutch version of the Apple Store. Although I understand Dutch, many don't, and English reviews are always welcome.
I'd switch to the US store if I could, but being my credit card Dutch, I'm out of luck.
Edit: I think I can't switch to US, not 100% sure.
Solution 3:
If your language is set to Finnish that means that like you said the app store will only show reviews from users that have set the same language.
So it really doesn't matter because no one from another country is going to read your review in Finnish and not know what it means.
Solution 4:
Yes. Well the problem is in bilingual countries, then it's not that simple and Apple's one country one language thinking goes a bit wrong. Since the IOS5 update my app store interface on my iPhone is in Finnish even though I have the language set to Swedish. I can imagine the same is true in other bilingual countries, like Canada, Swizerland, Belgium et.c. The app store interface should always be the same as the phone language is set to. If that language is not available it should default to English - Not to another language that happens to exist in the same country.