[jasonkester]

I guess it depends on the app, but be warned that performance of HTML5 on mobile devices such as the iPad is orders of magnitude worse than in native apps.

So even something straightforward like, say, smoothly animating a pinch zoom on an image, is just shy of impossible on a mobile browser. Add any complexity to your scene, then try to animate it and you'll quickly start reconsidering building a native app.

Sound is another non-starter in an HTML5 app. iPhone (& iPod touch) will only play audio fullscreen. iPad's Safari will play one audio clip at a time, but only as a direct result of a user action. Video is also out, since Apple devices will only play it fullscreen.

Depending on what you're building, you might not need any form of animation or sound. But if you do, now is not the time to make the move to HTML5 if you want your thing to work on mobile devices.

[illumen]

It's not that slow. I know this because I've done it. You just need to use the HW accelerated transforms/animations. They're pretty easy to use, and documented. There are some undocumented css things which cause slow downs though.

Animation is as fast as lightning, with expert timing. In fact it's a little bit frighting what you can do with it. If you use js setTimer based animation it's not that great though. You need to use the css animation stuff really.

Audio can be played with no user action - again I know this from direct experience.

Only the small devices play video full screen (currently... I can't comment on upcoming IOS releases ;). The ipad can play them without going fullscreen.

You can't just use links, with click events. Understanding how touch input works with multiple fingers moving on the screen, not waiting for releases is different than understanding interfaces with a big screen and one accurate mouse pointer.

Expect to pay top £/$ for good iOS html5/css/js/svg/canvas developers that also have experience on iOS/android/nokia/palm... if you can find them.

[Tichy]

Any idea where the market is for such developers? I intent to go the HTML app route, but I worry a little that I won't be able to get contracts for creating apps because I lack experience with the native side.

[jasonkester]

Hey, if you have a working example of two simultaneous audio clips playing in an iPad, run off a timer with no user click to initiate it, I'd absolutely love to see it and swipe the code. Ditto for smoothly panning and zooming a scene without the 'disappearies'.

That sort of thing is trivial in a browser, but it just falls down on apple devices. If you have counterexamples, you can save me a lot of grief, so please share them.

[nicw]

I agree with the above. Keep in mind that a lot of what you take for granted in a native app you'll have to build yourself. Scroll inertia, image carousels, determining a "flick" vs a tap, fixed tab bar - these are all something that haven't been 100% figured out. Yes, you can find solutions for each one, but try putting them all together and you quickly see the conflicts. Add in some caching of data and you'll learn that the HTML5 cache concept is different for each device.

I've tackled these issues personally, and at my company (iPad app). Keep in mind that your users will demand that your app at least feel native, if not the same UI controls. You think that you'll have the freedom to run on each platform, but in reality you'll be dealing with the quirks of each platform and that will set you back some dev time. Webkit is not 100% the same on each browser

What Phonegap gives you is a demarcation point to drop in your HTML code - and that's it. If you need API access for accelerometer, vibrate, etc then Phonegap can help. If your app is focused more on the user experience, then Phonegap cannot help you.

Do you really want to launch an app that will feel awkward on every platform, or just develop a native app for each major platform? That platform space isn't as large as you might think - iOS, Android, <pick your consumer markets third>

I'm a mobile product manager by day, my contact info is in my profile if you have any more questions.