> Now, let me think of some markup language that is universally known and has at least some pretence to be about laying out information on a screen... Thats rig

> Now, let me think of some markup language that is universally known and has at least some pretence to be about laying out information on a screen... Thats right, html. Sure, if you have low standards for UI. Ultimately making decent UI experiences cross-platform is impossible without some sort of catering to each platform that HTML/JS largely has no access to. React-native has made some headway here, as have electron + native bindings. But neither are really capable at this point of reproducing apps that clearly excel at leveraging platform-native frameworks.