For default in WordPress if you add a widget to the sidebar it is visible on every page. But sometimes it is necessary to show different widgets on the sidebars for some posts or pages.
Actually you can fully control on which pages your widgets will appear.
This 5 customize sidebar WordPress plugins enables you to customize the usage of different widgets in different sections, categories, posts, pages, and so on.
Use this plugin to create your own widgets, duplicate existing widgets and arrange them in a sidebar or anywhere else. Thanks to filter definitions you can decide whether the widget should be displayed or not for specific pages or page-types.
Show widgets in context – only on certain posts, front page, category or tag pages etc.
Dynamic Widgets lets you dynamically hide or show widgets on WordPress pages by setting conditional logic rules with just a few mouse clicks. You can set conditional rules by Role, Dates, Browser, Language (WPML or QTranslate), for the Homepage, Single Posts, Attachments, Pages, Authors, Categories, Archives, Error Page, Search Page and etc.
Custom Sidebars allows you to create all the widgetized areas you need, your own custom sidebars, configure them adding widgets, and replace the default sidebars on the posts or pages you want in just few clicks. You can also set new default sidebars for a group of posts or pages easily.
This plugin gives every widget an extra control field called “Widget logic” that lets you control the pages that the widget will appear on. The text field lets you use WP’s Conditional Tags, or any general PHP code. There is also an option to add a WordPress ‘widget_content’ filter — this lets you tweak standard widgets to suit your theme without editing plugins and core code.