> What have they been waiting for all this years?

Nokia bought Trolltech in early-to-mid 2008 (initial offer announced in January, purchase finalized in June). The iPhone SDK had been announced in October 2007 and been made available in February, Android 1.0 would only be released in September (though the beta had started in November 2007), the Windows 7 RTM would only happen in 2009 and W7P in 2010 so the Windows world was still "old windows" (on which regular Qt worked) and Windows Mobile 6.

One can easily assume that, as soon as the deal was announced and likely to go through, Trolltech had little reason to work on porting Qt to non-nokia platforms (out of the 2 months or so they'd have had for the Android beta, and negative 2 months for iOS).

And once Trolltech/Qt was part of Nokia, why would Nokia fund Qt/Android or Qt/iOS? The original plan was to build Nokia's own "next-generation platform" Maemo with it after all.

As to third parties, they did attempt porting Qt (ultimately fizzling out, for the most part):

* qt-iphone (Qt/Cocoa Touch) http://www.qt-iphone.com/Introduction.html

* Necessitas (Qt/Android) http://sourceforge.net/p/necessitas/home/necessitas/

> And once Trolltech/Qt was part of Nokia, why would Nokia fund Qt/Android or Qt/iOS?

Actually, I expected they'd do exactly that, and was disappointed when they didn't. It's basically the same reason why Sun created Java. They made Java so that software developers could make software that ran on Windows and Linux. Oh eh, and on Sun computers. Which were very much losing the server OS wars at the time. You might say that Java didn't save Sun, but I like to think that maybe instead Java postponed its demise by many years.

I think the same could've happened with Nokia. If Nokia sponsored the best way to make fast, snappy, great apps, in little time, that work comfortably and with a native feel on iOS and Android (oh eh, and also Nokia's current OS hobby), people'd churn out Nokia versions of their apps without much extra work. This might've significantly increased the app ecosystem for Nokia phones, which might have made more people buy the phones. A lot of people (and very much not just the geeks) do care that their favourite apps are supported and decent on a particular handset.

I never understood why they didn't do this. At the time when many developers were still a bit nervous about learning Objective-C just to support one single platform, a good, company-supported Qt-for-all-phones could've made Qt the leading app toolkit by far. Qt sure had the head start, Nokia sure had the resources, and the Qt team sure had the skills. Sad.

Were you following Qt closely, to know about all these Qt attempts? It's a shame that Qt on other platforms didn't work out... It would be a nice alternative to HTML5 and iOS and Android defaults.

I wonder if native UI rendering APIs will be available for these platforms. Will this be a simple wrapper and compile with few native hooks, like Flash on iOS? Or will they take a more integrated approach?

Qt without native UI isn't Qt. I am very interested to see how they will manage to handle the difference in UI concepts between the three mobile platforms.

I might be slightly out of date, but IMHO Qt has always only emulated the look and feel of the platform it was running on by painting all their widgets on their own. While the themes were certainly very good (much better, than, say Java/Swing's "native" themes), Qt apps still left that uncanny-valley feeling.

I can verify that your information is out of date. The widgets are to varying degrees actually native or drawn with OS functionality for drawing native widgets.

However, this is not all it takes to escape the uncanny-valley feeling. For example, the dialog layout still has to be correct, and lots of developers don't make the effort to achieve this.

I would have to second the developer problem. You can have a perfect cross platform UI toolkit, but if the developer doesn't take effort to make it fit everywhere it becomes off. A simple example was message box's. Qt has the ability for you to tell it which button is "yes" and which is "no" and then it will automatically swap the order depending on which desktop environment it is running in, but if the developer just hard codes some strings for the button text there isn't much that Qt can do. Same goes for file menu shortcuts, etc

How many times have you seen an app that is suppose to look 100% like an iOS app badly ported over to android where everything "works", but doesn't fit in.

Out of all the cross-platform toolkits Qt is the absolute best. For example, the Windows themes are literally flawless. It also takes into account so many things that other toolkits don't: native (file picker) dialogs, proper button order, paddings, etc.

That's because on Windows and OS X, Qt uses the operating system to paint native widgets, and uses the corresponding helper dialogs provided by the system.

Yeah, I want to see that too. The UI differences between the platforms go far beyond chrome and metrics. An app that runs on three platforms may have a different set of views and different navigation logic for each.

It's been possible to write Qt applications for Android for a while now: http://labs.qt.nokia.com/2011/02/28/necessitas/

Have you actually tried using that?

Its really hard to get running. Supporting android and allowing cross platform QT based applications would be an amazing step in the right direction for QT, and quite frankly, android.

Yes please!

Well the fact that Nokia bought it and did nothing with it for a few years certainly didn't help.

Nokia did excellent work on Qt 4.x, QtQuick/QML and QtCreator/QtSDK as well as a lot of the work for the upcoming Qt 5. Saying they did nothing with it for a few years isn't at all true and is not a fair statement as they did a lot of great work on Qt. Not to mention that they were the ones who released it under the LGPL!

Having said that, I'm both extremely happy and excited that Digia have bought Qt entirely and that they plan to support both iOS and Android, something I've been wishing would be supported for a couple of years now but didn't see as something that could happen under Nokia's ownership.