Mobile app with low page load times and broad browser support.

We want to build a mobile version of a popular classifieds site. Page load times must be minimal and have good mobile browser compatibility. We have an API that could potentially be used in an AJAX fashion. What would our best option (from experience) and why:

• HTML 5 app with ajax calls to the API for data.
• Plain HTML 4 site rendered server side.
• Full Javascript based app.
• ??

I've demoed several mobile framework, but they fee开发者_运维技巧l sluggish even on my iPhone 4.

You don't specify which frameworks you demoed... so I feel like I am suggesting something that you should already know about... anyway...

What about jQuery?

jQuery is a fast and concise JavaScript Library that simplifies HTML document traversing, event handling, animating, and Ajax interactions for rapid web development.

In particular, jQuery complies with the two requirements that you specified in the question title, since its library is a single JavaScript file and has a wide browser support.

As to performance, it is difficult to say anything without knowing exactly what issues you have had, or even what are your performance goals, but keep in mind that performance depends a lot on the code we write, more often than on frameworks, and with a so widely used framework as jQuery, you can be sure that there has been a lot of work done to make it performant. In any case, this link with some hints might be useful to give you an idea.