I remember the DS being my most capable portable computer. Seeing an emulator for it in the browser feels weird. (also, more on topic for your comment): Going

I remember the DS being my most capable portable computer. Seeing an emulator for it in the browser feels weird. (also, more on topic for your comment): Going the browser route now (counter intuitively) gives you more flexibility with language/tooling. I think as far as cooperate/closed source apps go the browser is absolutely the way to go. It's a very battle hardened sandbox and the W3c does a pretty good job accumulating portable standards for things. It even has push notifications and file I/O now (although Apple has been stingy with that.)