Agree, since the mobile devices can only natively play certain file types. I have transcoded my MKV and ISO files into MP4 files using the free program, Handbrake, found at https://handbrake.fr/ It’s easy – just use the default settings for iPad.
Also, since I have iOS phones and tablets, and Kindle (Android) tablets, I save the files as MP4 files and not M4V files, because a Kindle will not play files with M4V extension. These files are essentially the same, but the extension name is the key to the files playing or not on a Kindle. Also, any files I did have with the M4V extension could be changed to a MP4 and the files play on both iPad and Kindle tablets. An added plus is files made by Handbrake are much smaller than MKV file, yet their quality on tablets is stll very good.
