Toggle is a switch or lever that enforces a mutually exclusive state, either on or off. It is an incredibly simple UI component that can make a huge impact on user experience. Toggle switches can be used to update preferences, settings, or other types of information. Toggle switches should be accompanied by clear labels and standard visual design to maximize usability. Toggle switches should be placed on a page or app where users need to toggle between two opposing states such as allowing or disallowing cookies.
Toggles are also a great tool to leverage when managing changes to existing product features. They can be used to turn off specific parts of a feature in one release, while allowing the rest of the product to continue functioning as it always has. This can allow a team to evaluate the impact of a change in a controlled way before it is deployed to a larger population of users. Toggles can be used as a tool for Canary and Champagne Brunch releases.
Savvy teams view their Feature Toggle inventory as inventory that comes with a carrying cost and seek to keep that inventory low by being proactive about removing toggles that are no longer needed. Some teams even go so far as to put expiration dates on their toggles and use the CI/CD process as a means of automatically failing a test or refusing to start an application if a feature toggle has expired.
Managing toggle configuration via static files becomes cumbersome at scale. A common solution is to move the toggle configuration into some sort of centralized store, often an existing application DB. It is then possible for administrators, testers and product managers to manage the configuration of a set of toggles from a central location. This can significantly speed up the time it takes to re-configure a specific service instance and get it back into testing mode after a change is made.
It is important to test the toggle configuration that you expect to deploy in production. However it is also prudent to test a fallback configuration that has all the toggles you intend to release flipped Off. This will prevent unexpected regressions from sneaking in when a toggle is flipped On in production.
Color is an important signifier for toggles, but a designer must be aware of the societal and cultural implications of the choice. For example, using red for on can be counterintuitive for some audiences who associate it with stop signs and traffic signals. The use of a filled background for the on position can also lead to ambiguity as the user may think that the button is being pressed.
In addition to the above, many designers employ a combination of visual cues such as motion and the use of text to convey that the toggle is currently in an on or off state. Lastly, designers should test their toggles on a variety of screens and devices to ensure that they are easy to understand, readable and usable.
