Any example of app for OIN?

As I found out those examples from Okta are actually only for simple integration without OIN support.
But for OIN there’s no SDK can be used and a lot of certain nuances appear.
So hence the question is there any official/non-official example or sample app that’s shows how OIN Okta app should look lake at very basic lvl (at least for OAuth) ?

There’s a lot of theory in Okta dev center like OAuth flows etc that’s actually could be found everywhere on the Internet but there’s very little concrete info about implementation of integration with Okta especially for OIN support. That seems a bit strange for me, or maybe I missed something?

Thanks in advance.