Amazon AppStream is a fully managed application streaming service that allows users to access desktop applications from any device with an internet connection. It enables organizations to deliver applications securely to their employees without the need for local installations, making it easier to manage software updates and access. With Amazon AppStream, users can run applications in a web browser, providing a seamless experience across different platforms. This service is particularly useful for businesses that require remote access to software, as it enhances productivity while maintaining security and control over application usage.