Hello,
before iOS 11 we could upload only one app preview (video file) and only for the primary language (e.g. English). Other supported localizations used the app preview from the primary language. This meant we had to upload the app preview only once per each display size.
Now with iOS 11 not only can we add 3 app previews but we can add separate app previews for each supported language. My question is this:
I have an app that supports 4 languages on App Store - English as primary, French, Japanese and Russian. My app preview is language-universal (same video file for each language) but my screens are not (differen screen set for each language). Do I have to upload the same video file in every language? Or is it sufficent to upload the app preview only for English - e.g. if I don't upload the preview for French will the French App Store use the preview form English even though the "Use English (U.S.) [...]" checkbox is not ticked?
With the way iTunes Connect works (or often doesn't) uploading 3 files, 4 times each (12 uploads) might take half a day... and feels redundant.