Why does Javascript run so slow on iPhone?

Question

I\'ve been researching writing an app for iPhone. I really like the look of PhoneGap which basically allows you to contain a webpage in an app. My skills are primarially i

Answer 1

Javascript is not particularly slow, but the DOM is very slow.
I think it is the same as a desktop browser, but magnified.
I would check first all DOM manipulations, if they can't be optimized.

Another option, is to use a templating engine.
The main DOM manipulations are done through innerHTML injection, which is fast even on mobiles.

We've built a mobile version of our web app, and we use PURE (an open source JS lib we created) to render the HTML from JSON data, and it is very responsive.

We went the HTML5 way(not native) but I think generating the HTML could be done the same way when wrapped in PhoneGap.