In his article, Viktor Farcic discusses feature toggles versus feature branches within the context of a continuous integration framework. He talks about the pros and cons, rigidity versus flexibility, and how will feature toggles can fit into your continuous delivery process.
Feature Toggles (sometimes called Feature Switches or Feature Flags) should solve the need to be able to deploy only selected set of features while keeping only one (main) branch. With them we can do all the work in one branch, have continuous integration taking care of the quality of our code and use flags to turn features off until they are ready to be released. We can have all the benefits of Continuous Integration together with the flexibility to choose which features will be available and which will be hidden. Moreover, it is a step towards Continuous Deployment. If we do have satisfying automated test coverage and can switch features off and on, there is nothing really preventing us from deploying to production each commit that passed all verification. Even if some bug sneaks into the production, with Feature Toggles it would be very easy to turn that feature off until it’s fixed.
The basic idea is to have a configuration file that defines toggles for features that are pending to be fully released. Alternative to a configuration file can be a database table. The application should use those toggles to decide whether to make some feature available to the users or not. They might even be used to display some functionality to a subset of users based on their role, geographic location or random sample.