[junto]

I love Handbrake. It's my goto for video transcoding.

I often download stuff for my children from YouTube using a YouTube downloader, and then transcode them to the ideal iPad format, so the children can watch stuff in the car on the iPad without an internet connection. Great for long trips.

[pilif]

You could use youtube-dl and request the content in an iPad compatible format. It would save you the waiting time for the transcoding

[Veratyr]

If you get YouTube Red (which also saves the kids from ads), you also get offline support built into the mobile app. Just in case you weren't aware.

[kennell]

An iPad can't play regular MP4/H264 videos by default?

[evgen]

It can, but you can optimize the encoding so that the iPad needs to do less work playing the video.

[slhck]

Not all of them, at least. There are some restrictions with regard to profiles and levels that are supported (i.e. bells and whistles that the codec can use).