Series 40

The first Series 40 devices (introduced in 2002) had only 128x128 pixel large displays with lower color capabilities. Over the years, the S40 UI has evolved from a low resolution UI to a high resolution color UI with an enhanced graphical look. The third generation of Series 40 that became available in 2005 introduced support for devices with resolutions as high as QVGA (240x320).[6] It is possible to customize the look-and-feel of the UI via comprehensive themes. A list of all Series 40 devices can be found on the Nokia web site.

Series 40 is a software platform and application user interface (UI) software on Nokia's broad range of mid-tier feature phones, as well as on the Vertu line of luxury phones. It is the world's most widely used mobile phone platform and found in hundreds of millions of devices. Analyst estimates place the total number of devices shipped with S40 close to 1.5 billion, as of the end of 2010.

Platform provides communication applications such as telephone, internet telephony (VoIP), messaging, email client with POP3 and IMAP4 capabilities and Web browser; media applications such as camera, video recorder, music/video player and FM radio; and phonebook and other personal information management (PIM) applications such as calendar and tasks. Basic file management, like in Series 60, is provided in the Applications and Gallery folders and subfolders. Gallery is also the default location for files transferred over Bluetooth to be placed. Series 40 is an embedded software platform that is open for software development via standard or de-facto content and application development technologies. It supports Java MIDlets, i.e. Java MIDP and CLDC technology, which provide location, communication, messaging, media, and graphics capabilities. Flash Lite applications are also supported, but mostly used for screensavers.

The integrated web browser can access most web content through the service provider's XHTML/HTML gateway. The latest version of Series 40, called Series 40 6th Edition, introduced a new browser based on the WebKit open source components WebCore and JavaScriptCore. The new browser delivers support for HTML 4.01, CSS2, JavaScript 1.5, and Ajax. Also, like the higher-end Series 60, Series 40 can run the Opera Mini web browser to enhance the user's web browsing experience.

Support for SyncML synchronization with external services of the address book, calendar and notes is present. However with many S40 phones, these synchronization settings must be sent via an OTA text message.

Series 40 is a simpler operating system than the higher end S60 (which is based on the multi-tasking Symbian OS). Because S40 devices do not support true multi-tasking and do not have a native code API for third parties, its user interface may appear to be more responsive and faster than other Nokia platforms on similar hardware.