Now, we have the word from Joe Belfiore that Microsoft is indeed bringing FLAC support to Windows 10 for phones but not in the first preview build that will hit devices in February.
@Lisan_09 Yes, FLAC support will be on phones/small tablets… won’t be in the first insider build, though, will be a few months later..
— joebelfiore (@joebelfiore) January 28, 2015
This raises hope of native MKV support that is already present in Windows 10 Desktop to come over to Windows 10 for Phones.
Thanks Adil for the tip. Cheers!!