Symbian Series 60
Available on: A wide range of Nokia smartphones and some handsets from Samsung and Sony Ericsson
Current version: 9.4 (UI: S60 5th Edition)
Symbian is the most popular smartphone OS in the world and S60 is the user interface on most Symbian-powered smartphones, including the Nokia N97, Sony Ericsson Satio and the Samsung HD Icon. Now owned by Nokia, Symbian was originally a closed OS but it is now in the process of being open sourced. Smartphones running the Symbian OS are capable of multitasking and are compatible with Flash. Since the emergence of the iPhone and Google's Android many have criticised Symbian due to its steep learning curve and dated user interface. Symbian has a large developer community and a wide range of apps are available, but it doesn't have a central application store.
Strengths: Large developer community, compatible with Flash, multitasking
Weaknesses: UI not as polished as alternatives, often requires a steep learning curve to use, no central app store, the interface on touch-screen Symbian phones isn't as intuitive as competitors
Get it if: You like the interface of Nokia phones and you want the ability to customise and tweak your device
Avoid it if: You want a simple and hassle-free user experience, or you want a user-friendly touch-screen smartphone
Available on: A wide range of HTC, Samsung. Sony Ericsson, LG and Motorola smartphones
Current version: 6.5
Microsoft's Windows Mobile operating system was originally designed to provide a PC-like experience on your smartphone. The advantages of a Windows phone include mobile versions of Microsoft Office applications (Word, PowerPoint and Excel) and tight integration with the Outlook e-mail client. A wide range of other applications are available, including many business-focussed apps. However, Windows Mobile handsets have been plagued with outdated and unintuitive user interfaces and have often been criticised for being slow. The latest version, Windows Mobile 6.5, provides an intuitive home screen and a newly designed Start menu, but still lags behind most of the alternatives when it comes to usability. Manufacturers like Samsung, with the Omnia Icon and HTC, with the Touch Diamond2, have resorted to creating their own UI skins that sit on top of the Windows Mobile interface in order to provide a more intuitive user experience.
Strengths: Integration with Microsoft Outlook and Exchange, wide range of apps available
Weaknesses: Not as responsive, intuitive or user-friendly as the alternatives
Get it if: If you would like a Windows-style interface on your mobile phone and if you want seamless integration with Outlook
Avoid it if: You want a hassle-free user experience, you want an intuitive menu system and you prefer to not use a stylus
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