The traditional way of doing that has been to write a low-level C library with the core functionality, and write a native app for each platform that leverages t

The traditional way of doing that has been to write a low-level C library with the core functionality, and write a native app for each platform that leverages the library. This is how the best cross-platform apps are made. I can see a bright future tho in JavaScript-based game engines, so long as they're wrapped in a native app (written by a developer, not generated by an SDK).