At first (when it was still codenamed Hongmeng) it was nothing more than a crude android fork, but everything changed with version 2.x because they went from being a mobile operating system (android), to being a distributed operating system (HOS is platform agnostic), native (embedded) Javascript support and its own Typescript implementation ( eTS). And since version 3.x they are already rewriting the critical components (android core/APIS) to avoid legal conflicts with Oracle and western big techs, as well as the future migration to their own programming language: Cangjie (as far as I understand, very similar to Java/C#), so HOS as a future project will resemble a JVM/.NET on steroids and closer to be an universal system in many aspects.
Made in China. Hence the fear of the entire Western technology sector.
First blocking mastodon links, now this...
"GO TO HELL... YANKEES"
Hugo Chavez