Context Node allows you to select a predefined Context on each node. The functionality is already built in with Context but it would require a site manager to do so on a node by node basis.
With this module you can create as many contexts as you need and assign those context to a content type and let the user select a context.
Contex 3.x (both 6.x and 7.x versions)
1. Enable the module
2. Create as many contexts as you like. You can set Conditions but is not required. Set as many Reactions as you like, blocks, layouts, active theme, etc.
3. Configure your content type and enable as many contexts as you want to allow for this content type.
4. Set permissions.
5. Create a node and set a context from the list.
Differences between Context by node and Context Node
- Context by node allows you to create a context for each node. The context created will apply just for that node.
- Context Node allows you to select a predefined context when creating a node. That means, an admin must configure the contexts available and the content types where the user will use that context.