From the Qt website:
"Qt is a cross-platform application and UI framework. It includes a cross-platform class library, integrated development tools and a cross-platform IDE. Using Qt, you can write web-enabled applications once and deploy them across many desktop and embedded operating systems without rewriting the source code."
In the MeeGo context, Qt is the basis of the handset user experience; it is also recommended for developing MeeGo applications.
You can make use of a few additional frameworks (built on top of Qt) to make MeeGo development more convenient:
Qt Mobility provides APIs for mobile device development. This includes access to a device's data (for example, sensor data, location), as well as abstractions for telephony, connectivity, contacts, multimedia and other generic services. Qt Mobility also has adapters so it can be used with QML (see below).
MeeGo Touch Framework (MTF) is "a cross-platform application and UI framework library built on top of Qt". MTF helps when you're developing applications to fit with the MeeGo user experience model: it can assist in applying the MeeGo "look and feel", and its UI elements are optimised for touch. See MeeGo Touch Framework for details.
Qt development requires that you know one or two programming languages, depending on which elements you want to use:
For Qt (including Qt Mobility and MTF), you'll need to know C++.
You might hear the term Qt Quick in the context of MeeGo development. This term refers to using Qt and QML in an application, running under the QML runtime.
For each of the frameworks below, the main reference documentation site is listed, along with a few highlighted tutorials which are useful for getting started. The main API documentation site for MeeGo is http://apidocs.meego.com/.
QML (note: as QML is an add-on for Qt, its documentation is part of the main Qt documentation):
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