Transitions worked nicely, both meme and YouTube video thumbnail views were smooth. Compared to a possible native implementation the image search didn't work that smoothly during image loading, but it was still usable after all images were loaded. Also the list view for long lists with presumably dynamic loading (UITableView style) wasn't that smooth during scrolling.
All in all, kudos for the good work!
It is not so much about weather the UI is drawn so that it looks native and it is not about performance (although important). It is more about what you can and cannot do natively. For example, in iOS/Mac certain things are not easy to do because the UI components that you are extending are not designed to work in they way you want them to work. This may look like a limitation but I see it as an enabler because it forces applications to have more or less the same behaviour. This is what makes AppKit/Cocoa etc. a better platform for development on iOS/Mac.
Most of my friends use http://www.idangero.us/framework7/, which is also good and has many components. (Though I didn't really used it myself)
App.js doesn't look like it has enough components ATM.
What a mess the JS landscape is. There are so many frameworks, and no clear reason to choose one over the other. Angular has a reputation as being one of the better ones, but it seems overly complex, the documentation is terrible, and the learning curve is steep. And its still one of the better of the ones that I have tried.
If you pull a list down from the top or up from the bottom, the wrong thing scrolls. Not sure whether this is possible to work around.
iOS 7-style back gesture does not work.
In the input demo, pressing return on the Subject field submits the form. Demo bug?
Occasional popping when switching screens.
Nevertheless, seems pretty solid in general. I like it.
Just add this CSS:
* Fixed the scrolling issue. Ios safari doesn't let you disable the bounce so there is a workaround now.
* Ios back gesture works fine... Except in mobile safari, again because there is no way to disable apples back gesture. This would work best in phonegap or Kik where you can control these kinds of things
* Will fix subject bug in demo soon..
Famo.us is making the same mistake for some reason. Aggressively targeting mobile, with half of the toolchain missing to actually shipping mobile apps.
Not that I can blame the OP, who is likely not a SF startup with millions in funding.
The idea is that Kik's browser has the PhoneGap-like utilities that you described built-in, while this is a library for building the UI of an application. http://dev.kik.com/
Cross Two Platform.
What I'm saying is this is like a plain donut whereas a donut with sweet, sweet toppings already exists :D
There is also http://goratchet.com/components/
But then, the jailbreak scene came up and somehow Apple changed their stance by creating the app store and thus the possibility to control what kind of native applications will run on the devices.
Of course this way has the advantage of not needing a paid developer account or need to have the app approved by Apple but then again, such a webapp is harder to monetize if that's what you are after than to simply write a native app and sell it in the app store.