Google has broken out some Android accessibility features into a separate app. Switch Access has graduated from the Android Accessibility Suite and it's now available through the Play Store. Offering Switch Access features via a separate app could allow Google to roll out more frequent updates instead of having to do so at the OS level.
The move could also let Google offer Switch Access features on older devices too. The app is available on 2017's Android 8 (aka Android Oreo) and later.
Switch Access enables users to operate their phone or tablet using means other than the touchscreen, as Android Police notes. They can use the front-facing camera to control the phone with face gestures or external devices such as a keyboard or buttons connected via USB or Bluetooth. The on-board volume buttons can be used to control other aspects of your phone too.
Users can set up one or more switches (i.e. the front-facing camera and/or other devices) through the app. They'll be able to define how the app scans their screen for actions they're able to carry out. The app can move between all items one at a time, scan a single row at a time or select a location on the screen using moving lines.
Switch Access can also assign groups of actions to different switches. Press the corresponding switch for the color around the action you want to access, then keep narrowing things down until you get to the correct element. As 9To5 Google points out, once you select an item, several interaction options will be available, such as select, scroll, copy and paste. A menu at the top of the screen provides access to system-wide settings, notifications, the home screen and a way to record shortcuts for frequent and more complex actions.
To get started with Switch Access, go to the titular menu in the device's accessibility settings. The Switch Access app is free to download from the Play Store too.