I think the answer to all question/problem get mentioned in comments is WebOS or specifically ChromeOS.you have web cross platform app,without huge cost of brow

I think the answer to all question/problem get mentioned in comments is WebOS or specifically ChromeOS.you have web cross platform app,without huge cost of browser on top of os(so vendor can optimize the software stack very well).only problem with ChromeOS is non organized native app development.which could be solved by WebAsm.