I am about to start writing a web app for the latest smartphones using HTML5, CSS3 and JavaScript. I don’t need a framework so much as a library like jQuery.
I looked at jQTouch which is great for iPhone and apparently has support coming for Android too but I am looking to cover Blackberry device Software v4.6 upwards and WebOS 5 as well.
Does anyone have any ideas of alternatives to jQTouch or experience using jQTouch with Android's native browser, Blackberry's browser or WebOS native browser?
I did a project for Android and iPhone using jQTouch. There were times when I had to fiddle with the code to get it working correctly but as a whole I found that almost everything worked on iPhone and Android. Where I started having problems was that the Android browser doesn't have nearly as much support for CSS3/HTML5 (especially with animations) and the app ran much slower on android as the browser doesn't have hardware accelerated graphics. This was a while ago so hopefully it has matured a bit now.
Well you probably have to use jQuery. In the beginning of October, the jQuery community will release a jQuery Mobile Version, where you can use all the advantages of jQuery within almost every mobile browser. Check their site out: http://jquerymobile.com/
Sencha Touch is a possible alternative, but I have no idea how well it works on BB and WebOS. I'm afraid that you won't find something that works well with BB, since they have switched to a Webkit based browser only recently.
PhoneGap seems to be a reasonable cross-platform framework that supports encapsulating web app type development into an iPhone/iOS app, as well seeming to support some of the other platforms you asked about (but I have tried it on those).