A toggle is a switch that can be flipped to either state. It is the most common form of a user interface control that can be found in web and mobile apps. Toggles are used to update preferences, settings, and other types of information. Using toggles effectively requires designers to ensure that they provide direct labels, use standard visual design, and deliver immediate results. Toggles can be difficult for users to understand and evaluate, so color is often used to signal the current state. However, this practice can be counterintuitive to some users, especially if the toggle is being used by someone with red/green color vision deficiency.
Historically, toggles have been used as switches in mechanical devices to allow the operator to switch between two functions. For example, a toggle switch on a bicycle may allow the rider to change gears by pressing one of the levers. A similar switch in a computer can be used to switch between programs or between screen modes. The term “toggle” has also been used to describe software features that are able to be switched on and off, such as a toggle button for the Caps Lock and Num Lock keys on a keyboard.
When used in software, toggles are usually intended to be transitionary by nature and shouldn’t stick around for long periods of time (although product-centric toggles that stay in place for a few weeks or more are perfectly acceptable). In order to make sure that any changes to the toggling decision are rolled out correctly, the toggle configuration should always live side by side with the release version in source code. This allows developers to verify that the current release version is properly sending users down one of two codepaths (either an A or B) and can quickly revert back to a previous release in case of any issues.
Toggle switches are particularly useful in mobile applications, where there is typically limited screen space. The advantage of toggles in this context is that they can be implemented as tap-able elements and can replace multiple buttons on the page. This helps reduce the number of taps required to perform a task and also reduces the cognitive burden placed on users.
Despite the advantages of toggles, some developers prefer to use traditional checkboxes for forms that require multiple selections. While this can be a viable option, it is important to note that the toggle button may be more difficult for some users to understand and evaluate as it has a different visual appearance than a checkbox. This can be an issue for people with motor or cognitive disabilities, and should be avoided whenever possible.
A toggle switch is an essential user-interface element that should be used in most apps and websites. To ensure that users can easily understand and evaluate toggles, designers should be careful to avoid using confusing visual signals such as color or iconography and should only use them when they need to represent a simple contrast between opposing states.
