[chasil]

All of Android is still based on a pdksh-derivative known as mksh, which is an enormous install base.

http://www.mirbsd.org/mksh.htm

OpenBSD switched their default shell to their own pdksh-derivative known as oksh.

https://github.com/ibara/oksh

There was an effort to (re)start ksh93 development, but AT&T halted this effort. The bugfixes from the failed effort have moved back into Korn's last release.

https://github.com/ksh93/ksh/tree/dev