For the uninitiated, jQuery Mobile is a sweet little client framework that turns regular HTML into something more touch and mobile friendly. It results in a user interface that has bigger targets, rounded corners and simple skinning capability.

When it was announced that ASP.NET MVC 4 would include support for a mobile-sensitive view engine, offering up alternate views for clients that fit the mobile profile, I was all over that. Combined with jQuery Mobile, it brought a chance to do some experimentation. I blitzed through the views in POP Forums and converted them all to mobile views. (For the curious, this first pass can be found here on CodePlex, while a more recent update that uses RC 2 of jQuery Mobile v1.1.0 is running on the demo site.) Initially, it was kind of a mixed bag.

The jQuery demo site also acts as documentation, and it’s reasonably complete. I had no problem getting up a lot of basic views quickly, splitting out portions of some pages as subpages that they quickly load in. The default behavior in the older version was to slide the pages in, which looked a little weird when you were using a back button. They’ve since changed it so the default transition is a fade in/out. Because you’re dealing with Web pages, I don’t think anyone is really under the illusion that you’re not using a native app, so I don’t know that this matters.

I’ve tested extensively on iPad and Windows Phone, and to be honest, I’ve encountered a lot of issues. On Windows Phone, there is some kind of inconsistency that prevents the proper respect for the viewport settings. The text background on text fields (for labeling) doesn’t work, either. On both platforms, certain in-DOM page navigation links work only half of the time. Is this an issue of user error? Probably, but that’s what’s frustrating about it. Most of what you accomplish with this framework involves decorating various elements with CSS classes. There isn’t any design-time safety to speak of to make sure that you’re doing it right.

I think the issues can be overcome, but there are some trade-offs to consider. The first is download size. Yes, the scripts and CSS do get cached, but that first hit will cost nearly 40k for the mobile parts. That’s still a lot when you’re on some crappy AT&T EDGE network, or hotel Wi-Fi.

Then you have to ask yourself, do you really want your app to look like it’s native to iOS? I’m not saying that’s a bad thing, because consistent UI is good, but you will end up feeling a whole lot of sameness, and maybe you don’t want that. I did some experimentation to try and Metro-ize the jQuery Mobile theme, and it’s kind of a mixed bag. It mostly works, but you get some weirdness on badges and with buttons that I’m not crazy about. It probably just means you need to keep tweaking.

At this point, I’m a little torn about whether or not I’ll use it for POP Forums or one of the sites I’m working on. The benefits are pretty strong, but figuring out where I’m doing it wrong is proving a little time consuming.