www.makemkv.com

Are these files playable on Apple devices? iPhone, iPad?
Thanks.

With Apple software? No.

Apple does not seem to acknowledge the existence of MKV files. In fact, they've required that vendors of software in their app store to remove support for the audio used on DVDs, unless they prove that they have a licensed decoder, even though non-infringing, open-source decoders exist. Apple's QuickTime software for OS X and Windows will also not play MKV files without third-party add-ons.

However, MKV files can be the first step towards playing your DVD/BD collection on Apple devices. There ARE third-party apps that play the files. And there are programs for Windows, OS X, and Linux that can convert MKV files into something that Apple does support.

VLC on iOS plays MKV just fine despite Apple being stubborn about it.