Symbian for Software Leaders: Principles of Successful Smartphone Development Projects

Chapter 2. The big picture of a Symbian OS project

High-level components of a smartphone

A product based on Symbian OS typically includes, and interfaces with, numerous software and hardware components. This is true whether the product is:

• An entire smartphone

• Designed to be used in conjunction with existing smartphones, as an "add-on"

• Designed to be incorporated in forthcoming new smartphones, as a "build-in".

In all three cases, it is important to understand the relationships between the high-level components that make up a smartphone. From the point of view of a Symbian OS project, these components include the following:

• The silicon chips on the phone – including the "application processor" (AP) and the "baseband processor" (BP); note that these are sometimes combined into a single chip

• A wireless signaling stack, running on the baseband processor, which talks to the wireless network and implements the GSM and/or CDMA protocols

• Symbian OS itself, running on the application processor

• Communications between the two main chips (often known as "ISC" – "Inter Systems Communications")

• Graphics, audio, and other multimedia components (often including many software plug-ins to implement specific items of multi-media functionality)

• Other aspects of the hardware design of the phone – including keypad, antenna, battery, etc.

• The UI system – such as UIQ, S60 from Nokia, or the FOMA UI used by NTT DoCoMo phones

• Third-party applications

• Third-party software that enables extra applications.

Upwards of a dozen ...