Series 60

The S60 Platform (formerly Series 60 User Interface) was a software platform for smartphones that runs on the Symbian operating system. It was created by Nokia in 2001, and was first released in 2002 with the Nokia 7650 smartphone. The platform has since seen 5 updated editions. Series 60 was renamed to S60 in November 2005. It was essentially a user interface able to access the core Symbian OS.

In 2008, 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. Subsequent iterations were named Symbian^2 and Symbian^3.

The S60 software is 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.

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