I mean, what's better with JS than Objective-C with Xcode?
Cross-platform portability, for one. I know it's a long way off, but being able to use JS as a first-class language on all mobile platforms would be a fantastic step forwards.
IMO, it would be better to hire another Android developer with saved cost.
And why should we step to a language which cannot offer any benefit? Even if it happen, it seems just a huge step backward.
For portability, I don't think JS is portable. Because portability doesn't come from a language. It comes from implementations by platform vendors. It's purely up to how platform vendors support the compatible language and feature set implementation. JS itself has nothing special in portability. Though all the browser vendors are supporting JS, it doesn't mean native platform vendors are interested in JS.
For the real serious portability, I think the only choice are C/C++ which are the CURRENTLY AVAILABLE de facto portability layer on ANY platform while keeping most of the benefits I mentioned. Including mobiles, desktops, servers, game consoles, embedded devices and even on web-browsers. And also for any new unknown future platforms. C/C++ support is virtually promised due to its superior range of existing portability.
And intermixing them with Objective-C is literally natural, and far easier then JS.
Cross-platform portability, for one. I know it's a long way off, but being able to use JS as a first-class language on all mobile platforms would be a fantastic step forwards.