4.2. CLIENT SIDE
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Siemens(8,4%) and Sony Ericsson(13,1%). There are many reasons to why this OS is so popular, the most important ones are probably its architecture and openness. Symbian has a plug-in architecture which makes it easy for manufacturers to add their specific functionality on top of the OS, for example to support device differentiation. It is also referred to as an open OS. Symbian is not open source, but it is open in the way that its APIs are public available. Due to its popularity the platform has become a target also for various viruses. Applications can be developed using several programming languages, these include Java, C++, C# (Symbian version, plug-in available for Microsoft Visual Studio). Microsoft Windows Mobile Microsoft’s mobile OS is called Windows Mobile. Currently, they have just released version 6.0. The OS can be seen as a subset of the normal Microsoft Windows operating system for desktop and laptop computers, and comes in two flavours; a smart phone edition and a pocket pc edition. Both versions include support for multimedia such as media player and instant messaging. In addition to this, the pocket pc edition also includes PDA releases of the popular word processing program Microsoft Word and Microsoft Excel. The operating system supports multitasking and is one of the most popular mobile operating systems in the United States of America today. One of the reasons for its popularity is that the transition to using a mobile device is easy because of the similarity to a desktop computer (e.g. start button). The primary programming language for applications running on the Windows Mobile platform is Visual C#, it is also possible to use Visual C++ and Visual Basic .NET. PalmSource Palm OS is well established among mobile users, being the first commercially successful OS for PDAs. Today it can not compete with new systems such as Symbian and Windows Mobile, because it lacks support of multitasking, 3G and more. Despite of its limitations, it is by many considered to be the most easy-to-use operating system available for mobile devices. The Palm OS is mainly developed as a personal organiser, thus it is not like a standard computer OS. It focuses on the management of an owners personal information like contacts, calendar and tasks. As mentioned the Palm OS up to version six does not support multitasking, which basically means that an application closes instead of running in the background as on Microsoft Windows Mobile. Consequently, the user is not able to swap between running applications, which is possible on a desktop computer. Devices running Palm OS are best suited for users that plan on using their device for personal organisation only. RIM Research In Motion (RIM) is the number one smart phone producer in the United States of America and number four mobile operating system in the world [25]. Their product is the Blackberry16 and focus on providing the business user with applications that go beyond just reading emails. The latest release of Blackberry supports a total of more than 1500 business applications. They are all written in Java making it possible to run them on various models and work over different cell technologies. 16
http://www.blackberry.com/