A toggle is a switch that can be used to select between two states or options. Toggles are commonly found in everyday technology devices like smartphones and tablets to enable or disable features and settings. They are also used in software applications to provide users with different display modes and other user experience customizations.
The word toggle is also used to describe the process of switching between programs or settings, such as the use of the keyboard shortcut Alt+Tab in Microsoft Windows. The term can also be used to refer to a physical button or switch that can be pushed or pulled to change the function of a machine, such as an electric switch or a light bulb.
When it comes to application development, toggles are used to allow developers to implement a variety of changes to the UI without having to deploy new code. This can be helpful when testing or introducing a new feature that may not work as intended in production and to help avoid unintentional regressions.
One of the most common uses for toggles in application development is for experimentation and testing. By enabling a new feature or change with a feature toggle and then allowing only a subset of the user base to access it, developers can quickly measure how well a particular feature is received by their users. This practice is often called Canary Release or Champagne Brunch and it can dramatically reduce the risk that a new release will be met with widespread user rejection.
Another common use for toggles is in the form of permission control. Many applications have features that are locked behind a paywall and only available to premium users. By implementing a toggle that can be flipped on or off by the application owner, they can limit which users are exposed to these premium features. This can help prevent a negative user experience by only showing the premium features to users who have paid for a subscription.
Lastly, toggles are sometimes used to provide users with a selection of themes in an application. This can be helpful for users who want to customize their experience based on their personal preferences or reading habits. In these cases, it is important for designers to ensure that the toggles are clearly labeled and utilize visual cues to avoid confusion for users. For example, the labels on a toggle should be clear and direct, and designers should not rely too heavily on color alone to convey meaning as this can cause issues for people with color vision impairments.
When it comes to testing a toggle-based release, many teams recommend that they test both the current production toggle configuration as well as the fallback toggle configuration with all of the switches flipped Off. This can help to avoid any unexpected regressions in a future release and is especially useful when teams follow the convention of having existing or legacy behavior enabled when a toggle is flipped Off, and new or future behavior enabled when a toggle is flipped On.
