The Expo SDK provides access to device and system functionality such as contacts, camera, gyroscope, GPS location, and so on, in the form of packages. You can install any Expo SDK package using the npx expo install command. For example, three different packages are installed using the following command:
Every quarter there is a new Expo SDK release that typically updates to the latest stable versions of React Native and React Native Web, and includes a variety of bug fixes, features, and improvements to the Expo SDK.
Packages in the Expo SDK are intended to support the target React Native version for that SDK. Typically, they will not support older versions of React Native, but they may. When a new version of React Native is released, the latest versions of the Expo SDK packages are typically updated to support it. However, this may take weeks or more, depending on the extent of the changes in the release.