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Platform

S60 3rd Edition uses the EKA2 real time kernel. The Series 80 platform uses the EKA1 kernel, which has poorer performance for time-critical applications. The startup code for applications is different as a result of the different kernels.

• S60 3rd Edition has added platform security. The main areas of this are data caging, capability model, and the Symbian Signed process. Data caging affects the file structure and prevents access to files and resources from executables or processes that are not trusted. The capability model is the method by which executables and processes can become trusted. The Symbian Signed process provides digital signatures for installation files, these signatures determine the capabilities granted to the executable.

• S60 3rd Edition does not use the sysAgent as in the Series 80 platform. Instead, the publish and subscribe method is used to share non-persistent global data between processes.

• S60 3rd Edition does not use the sharedDataKeys as in the Series 80 platform. Instead, the central repository is used for storing persistent keys.

• S60 3rd Edition does not have recognizers as in the Series 80 platform. Instead, the ECOM plug-in framework is used.

Hardware

Devices based on the S60 platform have a small screen and an alphanumeric keypad, and are optimized for one-hand use.

Series 80 devices have a significantly larger screen and a full QWERTY keyboard, as seen, for example, on the Nokia 9300 and 9500 Communicators.

The standard S60 screen is 176 pixels by 208 pixels but S60 3rd Edition introduces new screen resolutions and APIs to support the scalable UI. Scalable UI allows applications to be developed without being tied to a particular screen size. Any S60 application should now support the following screen resolutions:

• 176 x 208 – standard

• 240 x 320 – quarter VGA (QVGA)

• 352 x 416 – double resolution

In addition to the traditional S60 portrait layout, landscape layout is also supported in the double resolution (352 x 416) and QVGA (240 x320) modes. The Series 80 screen is 640 pixels by 200 pixels and always uses a landscape layout.