QtMobility Reference Documentation

Qt Mobility Project Reference Documentation


Introducing the QtMobility Project APIs

The QtMobility project covers a diverse range of features and technologies. It is not a single API but a collection of APIs and frameworks.

This release contains the following APIs:


The Connectivity API facilitates communication with local devices.


An API enabling clients to request contact data from local or remote backends.

Document Gallery

An API to navigate and query documents using their meta-data.


An API enabling a client to provide tactile and audio feedback to user actions.

Location API

The Location API provides a library for location positioning, landmark management and mapping and navigation.


The Messaging API enables access to messaging services.


Provides a set of APIs to play and record media, and manage a collection of media content.


An API enabling clients to request calendar, schedule and personal data from local or remote backends.

Publish and Subscribe

The Publish and Subscribe API, containing Value Space, enables applications to read item values, navigate through and subscribe to change notifications.

Qt Service Framework

A set of Qt APIs to that allows clients to discover and instantiate arbitrary services.

QtMobility QML Elements

A list QtMobility QML elements.

QtMobility QML Plugins

A set of QML compatible plugins for the QtMobility Project.


The Sensors API provides access to sensors.

System Information

A set of APIs to discover system related information and capabilities.


An API to import and export to the vCard and iCalendar formats.

These APIs give the developer a range of desirable functions for a mobile platform, but now these functions become possible on platforms not traditionally associated with some of the features. A mobile device using the QtMobility Project API would be able to

  • Locate services on-board or remotely. Find an optimal connection to the network for the particular service.
  • Services built on top of these APIs would include Internet applications such as email and web browsing.
  • Multimedia features enable image and video capture with audio , audio recording, and the playing of music or video clips.
  • Location will make the device aware of its geographical location to support GIS applications.
  • Publish-Subscribe enables communication between separate objects whether local or remote to the device.

The New Qt APIs deliver to developers an enabling package. It will be used by developers to build a variety of applications and services that are mobile capable or familiar to mobile users, irrespective of whether the platform is mobile or not. This means that there is the possibility of easy transfer of user experience from PC to phone or vice versa.

Getting Started

To get started with QtMobility see the

For users on the supported Symbian platforms, shown at the bottom of this page, see the instructions at the Qt For Symbian Developer's Library

Known Issues

See Release Notes.

For an overview of Platform Compatibility see Platform Compatibility.

The QtMobility APIs

Service Framework

A platform independent method of finding Services. A 'service' is an independent component that allows a client to perform a well-defined operation.

The services are implemented as plugins installed on the device and can look for supporting external services running on a central server. E.g. weather, local tourist attractions etc. Default applications can use the layer to locate servers.

Since this is an abstraction layer then the app does not need to be concerned with the underlying protocol, where the servers are, the hardware peculiarities with networking and other low level details.

For more details see the Service Framework API overview.


A common interface for handling SMS, MMS, MIME Email and TNEF Email messages. Enables access to messaging services to search and sort messages, notify of changes to messages stored, send messages with or without attachments, retrieve message data, and launch the preferred messaging client to either display an existing message, or compose a message.

For more details see the Messaging API overview.

Bearer Management

[ This API is now deprecated. ]

Although not a network manager, this component manages the connectivity state of the device to the network. So it does not manage network configurations, which are the role of the platform provider, but it does allow the user to start or stop network interfaces. Some higher level management of the connection session may also be possible as well depending on the platform.

Some platforms can have a set of grouped access points perhaps based on a common purpose. Bearer Management allows comparison and prioritization of the access and use of these points.

The aim of Bearer Management is to reduce the need for the developer to be concerned about trying to locate the best connection from a list of possible IP bearers and 3G connections. The user can select the best or it can be selected transparently so that WLAN roaming can occur seemlessly.

Some examples of the Bearer Management functionality,

  • On demand use of the appropriate Access Point. When a user starts to use a browser, the appropriate access point is selected from those available and a connection is transparently made.
  • Always-on applications such as email or IM roam automatically between cellular packet data and WLAN networks. The application developer is in control and for example the application can gracefully close TCP connections over the old bearer after setting up new TCP connections over the new bearer.
  • Application developer can create a settings user interface, where the user can select a certain connection to be used with the application
  • A connection manager application can be implemented with Qt. This application enumerates available connections, shows counters, and allows the user to connect or disconnect

For more details, see the Bearer Management API overview.

Publish and Subscribe

Will enable context sensitive access to information in future releases. Data is organized as a tree, with data being able to 'shadow' other data with the 'same key', a string specifying the leaf or node. The context is an example of a context ontology, a defined set of relationships. As the context changes the values of the objects change but the relationships remain the same. It is intended to be an enabling technology, the basis of a range future applications.

At this stage the API is intended to act as a common communications method between applications, whether local or remote.

For more details, see the Publish and Subscribe API overview.


The structure and retrieval of contact data from local or remote backends. It includes the ability to create, edit, list, delete and lookup contact information whether it is stored locally or remotely.

For more details, see the Contacts API overview.


The location API is composed of 3 components. Location positioning, landmarks, and mapping and navigation. The location positioning API provides an easy to use interface that encapsulates basic geographical information obtained from satellite or other sources about the user, including latitude and longitude, bearing, speed and altitude. The Landmarks API allows storage and retrieval of points of interests while the Maps and Navigation API provides mapping, geocoding and routing functionality.

For more details, see the Location API overview.


An API to play audio and video of various formats. Record audio. The playing and managing of an FM radio. This includes the typical functionality you would find on a music and video player, combined with an FM radio.

For more details see the Multimedia API overview.

System Information

An API to discover system related information and capabilities. Information available will cover software version numbers, hardware features, network connection types and status, display, data storage devices, device information and the screensaver.

For more details see the System Information API overview.


An API for accessing hardware sensors. This covers both high-level sensors such as screen orientation (portrait, landscape) and low-level, real-time sensors such as accelerometer data.

For more details see the Sensors API overview.

Versit (vCard)

An API to manage Versit ® documents, such as vCards.

For more details see the Versit API overview.


An API for management of calendar, scheduling and personal data from local or remote backends. It includes the ability to create, edit, list, delete and lookup organizer information whether it is stored locally or remotely.

For more details, see the Organizer API overview.

Versit (Organizer)

This is a continuation of the Versit API to interface the Organizer API with iCalendar documents using the same framework as for vCards.


The Camera API provides control of system camera devices. Providing support for still or video image capture with sound support. This functionality is part of the Multimedia API.

For more details, see the Multimedia API overview.


The Landmarks portion of the Location API facilitates the creation, retrieval, updating and deletion of landmarks from arbitrary data stores.

For more details, see the Landmarks API overview.

Document Gallery

An API for accessing collections of documents and media and their meta-data.

The Document Gallery provides an interface to a searchable index of document meta-data. The gallery may be queried to discover the meta-data of documents, or to discover documents with desired meta-data.

For more details, see the Document Gallery overview.


The Feedback API enables a client to control the vibration of the device or the piezo feedback from the screen.

For more details, see the Feedback API Overview.

QtMobility QML Plugins

The various APIs that constitute QtMobility are have QML interfaces to give non-C++ developers the opportunity to produce applications that utilize the power of Qt and QtMobility.

The QtMobility Namespace

The QtMobility APIs are placed into the QtMobility namespace. This is done to facilitate the future migration of QtMobility APIs into Qt. See the Quickstart guide for an example on how the namespace impacts on application development.

Platform Compatibility

Color Explanation
A functional backend for the API on the platform is complete.
A functional backend for the API on the platform is being worked on, however it is not functionally complete.
A functional backend for the API on the platform is being worked on. At this point it is far from functionally complete or there is no platform specific code inside QDF source code.
A functional backend for the API on the platform is not being worked on. It is possible for others to implement and integrate support. Alternatively, the platform does not support the feature.

Tier 1 Platforms
QtMobility API development focuses on Nokia platforms. These platforms are part of our ongoing QA, which includes unit test coverage per API and rigorous testing via test utilities and other system test processes.
Tier 2 Platforms
These platforms are not currently under active development or QA. Contributions to these platforms are welcome.

  API Maturity Level Tier 1 Platforms Tier 2 Platforms
S60 3rd Edition, Feature Pack 1 S60 3rd Edition, Feature Pack 2 S60 5th Edition Symbian Maemo 5 Harmattan MeeGo Windows XP/Vista Linux Mac OS X Blackberry
Service Framework FINAL
Messaging FINAL
Bearer Management FINAL 3)
Publish and Subscribe FINAL
Contacts FINAL
Location FINAL
Multimedia FINAL
System Information FINAL
Sensors FINAL
Versit(vCard) FINAL
Versit(Organizer) FINAL
Camera FINAL
Organizer FINAL
Landmarks FINAL
Document Gallery FINAL
Maps/Navigation FINAL
Feedback FINAL 1) 1) 2)
Connectivity (Bluetooth) FINAL
Connectivity (NFC) FINAL

1) S60 3.1, 3.2 no ramp up/down for attack/fade.

2) S60 5 only vibration available.

3) QtMobility Bearer does not support MeeGo. Use Qt 4.7 based Bearer API instead.

Feedback and bug reports

Email any inquiries and feedback about QtMobility to qt-mobility-feedback@trolltech.com

And please report any bugs you may find to http://bugreports.qt.nokia.com


The icheck tool uses the following third-party component:

Open Source front-end for C++ (MIT license), Roberto Raggi <roberto.raggi@gmail.com>, QTMOBILITY/tools/icheck/parser/src


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