If you are considering to develop an application for the Symbian platform there is a great chance that you have been recommended (especially by Nokia) to use Qt for the task. I have a somewhat different recommendation for you, I actually advise to use eSWT and MIDP.
It is true that Qt will be the primary technology for applications starting with Symbian S^4 release. However, according to the Symbian roadmap, S^4 release is due end of this year, and the handsets based on the release will start to sell on 2011. The good people on the Qt software actually made the Qt 4.6 release compatible with Symbian/S60 devices with the 3rd Ed. FP1 and later releases. Furthermore, .sis packages that you can bundle with your application for those earlier platforms are available. Of course, that means that you need to get your users to install a few MBs of Qt with your application. Naturally, you may actually assume that a Qt based application would have the benefit of covering both Symbian and Nokia's exciting new Maemo based devices. That is not entirely possible either because both platforms have chosen not to use Qt's widgets (QWidgets ) and build their own separately (which is explained better here).
On the other hand, eSWT is available on board for all the S60 3rd Ed FP2 and later devices and will continue to exist on Symbian S^4 based devices, so your application does not need to bundle any additional .sis files. Although we are adding new features on Symbian S^4 release, eSWT API is always backwards compatible and your code will work. I believe eSWT together with MIDP provides a good and lasting solution if you are targeting Symbian devices. _Unfortunately, eSWT solution is not without its flaws as well. eSWT is not as feature rich as Qt. Although eSWT will be adding new features constantly, eSWT team and Nokia investment on eSWT is tiny compared to Qt so it will not get as feature rich as Qt anytime soon. Tooling support is lacking with eSWT. It is the MIDP Java tooling so you will not get visual editors as you would with Qt. Although Qt's documentation may seem better than eSWT, I think SWT documentation will help you most of the time. And yes, Qt is in fact the determined future platform for Nokia and Symbian.
If I was given the task of developing an application for Symbian today, I would first look at eSWT and Java MIDP to see if that satisfies my requirements and use them if it does. And I would asses if It would be beneficial to make a Qt version of my application when Symbian S^4 becomes available.
It is true that Qt will be the primary technology for applications starting with Symbian S^4 release. However, according to the Symbian roadmap, S^4 release is due end of this year, and the handsets based on the release will start to sell on 2011. The good people on the Qt software actually made the Qt 4.6 release compatible with Symbian/S60 devices with the 3rd Ed. FP1 and later releases. Furthermore, .sis packages that you can bundle with your application for those earlier platforms are available. Of course, that means that you need to get your users to install a few MBs of Qt with your application. Naturally, you may actually assume that a Qt based application would have the benefit of covering both Symbian and Nokia's exciting new Maemo based devices. That is not entirely possible either because both platforms have chosen not to use Qt's widgets (QWidgets ) and build their own separately (which is explained better here).
On the other hand, eSWT is available on board for all the S60 3rd Ed FP2 and later devices and will continue to exist on Symbian S^4 based devices, so your application does not need to bundle any additional .sis files. Although we are adding new features on Symbian S^4 release, eSWT API is always backwards compatible and your code will work. I believe eSWT together with MIDP provides a good and lasting solution if you are targeting Symbian devices. _Unfortunately, eSWT solution is not without its flaws as well. eSWT is not as feature rich as Qt. Although eSWT will be adding new features constantly, eSWT team and Nokia investment on eSWT is tiny compared to Qt so it will not get as feature rich as Qt anytime soon. Tooling support is lacking with eSWT. It is the MIDP Java tooling so you will not get visual editors as you would with Qt. Although Qt's documentation may seem better than eSWT, I think SWT documentation will help you most of the time. And yes, Qt is in fact the determined future platform for Nokia and Symbian.
If I was given the task of developing an application for Symbian today, I would first look at eSWT and Java MIDP to see if that satisfies my requirements and use them if it does. And I would asses if It would be beneficial to make a Qt version of my application when Symbian S^4 becomes available.
