HarmonyOS Next (which I guess is 5). A chinese guy I met at the airport showed to me very proudly how amazing Chinese-made tech was. I will say the software looked polished enough and surprisingly good, yet it felt totally just like a hard android-based OS (which I bet it is).

Some might argue that the software has enough changes in it to be considered a distinct OS, but I'd rather just call it a hard fork as I had the impression that this was a more accurate depiction of what's really going on behind the scenes.