If you have designed your application to have its own settings view, you can centralise this view in the Nokia N9 Settings system. Your users can then access your application's settings via the Settings application, which is available in the Applications view.
In the settings view, you can group related settings together with visual dividers. Each group can contain multiple items, e.g. text, images, and buttons.
However, if your users can change settings directly on the UI, you should not include those settings in the settings view. For example, if the user can set a clock alarm directly in the main view of the clock application, then there is no need for you to include the alarm setting in the clock settings.
Note that when a user changes his or her settings on the device, the change happens in real time, and there is no need to 'save' these changes.