First two levels are just fine. Third level starts requiring the typing of Yiddish characters which do not appear in the virtual keyboard (פֿ so far, but probably others later). I can type it using my personal keyboard, but it would be great to have the virtual keyboard available for those who have not installed a Yiddish/Hebrew keyboard. Since the course says “STILL UNDER CONSTRUCTION,” I’m hoping Mr. Zebra 
is still around to do something about it (although I have no idea how long ago this was started). I’d love to be able to recommend this course to some new Yiddish students. It could be a really great resource. Thanks