Fun question although probably not really on topic.

NetHack

MUDs, MOOs, MUSHs

Dwarf Fortress

Kroz

Brogue

Zork (looks best on green phosphor screen).

Midnight Commander.

Trade Wars 2002.

If you explore the right platforms and eras then you will find many tens or even hundreds of thousands of text applications, many of which look "good" in my opinion.

Command-line tools?

mutt, irssi, newsboat, vim ... ¯\_(ツ)_/¯

manuw - random-ish question i saw somewhere that u were using minikeepass which is deprecated on ios -- any suggestions? what are you thinking of using?

ah oops... i meant mobile apps

I think most text-only user interfaces look good. Ones with graphics and fancy styling varies more widely.