S60 (software platform)

The S60 Platform, originally named Series 60 User Interface, is a discontinued software platform and graphical user interface for smartphones that runs on top of the Symbian operating system. It was created by Nokia based on the 'Pearl' interface from Symbian Ltd. S60 was introduced at COMDEX in November 2001 and first shipped with the Nokia 7650 smartphone; the original version was followed by three other major releases.

In 2008 after Nokia bought out Symbian Ltd., the Symbian Foundation was formed to consolidate all the assets of different Symbian platforms (S60, UIQ, MOAP), making it open source. In 2009, based on the code base of S60, the first iteration of the platform since the creation of Symbian Foundation was launched as S60 5th Edition, or Symbian^1, on top of Symbian OS 9.4 as its base. Subsequent iterations dropped the S60 brand and were named solely under the Symbian name.

The S60 middleware was a multivendor standard for smartphones that supports application development in Java MIDP, C++, Python and Adobe Flash. Its API was called Avkon UI. S60 consists of a suite of libraries and standard applications, such as telephony, personal information manager (PIM) tools, and Helix-based multimedia players. It was intended to power fully featured modern phones with large colour screens, which are commonly known as smartphones.

Originally, the most distinguishing feature of S60 phones was that they allowed users to install new applications after purchase. Unlike a standard desktop platform, however, the built-in apps are rarely upgraded by the vendor beyond bug fixes. New features are only added to phones while they are being developed rather than after public release. Certain buttons are standardized, such as a menu key, a four way joystick or d-pad, left and right soft keys and a clear key.

S60 was mainly used by Nokia but they also licensed it to a few other manufacturers, including Lenovo, LG Electronics, Panasonic, Samsung, Sendo, Siemens Mobile, Sony Ericsson, Solstice and Vertu. Sony Ericsson notably was the main vendor using the competing UIQ Symbian interface.

In addition to the manufacturers the community includes:

There have been four major releases of S60: Series 60 (2001), Series 60 Second Edition (2002), S60 3rd Edition (2005) and S60 5th Edition (2008). Each release had an updated version called Feature Pack, sometimes known as relay. Each runs on top of a different Symbian OS version.

As an OS, Symbian OS originally provided no user interface (UI), the visual layer that runs atop an operating system: this was implemented separately. Other than S60, other examples of Symbian UIs were MOAP; Series 80; Series 90 and UIQ. This separation of UI from underlying OS created both flexibility and some confusion in the market place. The Nokia outright purchase of Symbian in June 2008 was brokered with the involvement of the other UI developers and all major user interface layers had been (or pledged to) donating to the open source foundation, Symbian Foundation, who would independently own the Symbian operating system. It announced its intent to unify different Symbian UIs into a single UI based on the S60 platform.