I'm curious what the best way to develop software for ChromeOS is that's not writing a web app. It can run Android apps, right? With the Linux support can it run anything else, like X apps, or is it restricted to Chrome and Android?
Get hired by Google to work on Chrome OS. Certainly the best way. Afraid is also the only way.
More seriously. Chromebook have several native apps. The browser, the file browser the gallery app, the movie player.. and that's all I guess.
There is chromebrew but it requires you to put the device in dev-mode and it very niche.
The are some PWA which seem to work only with Chromebooks, but that's different I guess.