Exporting as a moviefile (MP4 or Quicktime Prores) will be implemented very soon.
But that doesn’t help you now of course. 😉
So you need to export as a sequence of png files (make sure “Simple Unbroken Sequence” is checked) and then you can use some other software that can convert your sequence of png’s to, say, an mp4. The mp4 format is excellent for sharing.
If you don’t mind using the terminal/shell, I can recommend using the command ffmpeg. You need to download and install it first. You get it for free here: https://ffmpeg.org
The command will look something like this:
ffmpeg -framerate 12 -start_number 1 -i /inputpath/basename.%04d.png -vcodec mpeg4 /outputpath/youranimation.mp4
ffmpeg has tons of options to explore. I’m thinking the above command is fairly self explanatory. Let me know if you need any help with it.