An item that can have children items. Only one additional level is permitted. Multiple accordions can be grouped so that only one accordion in the group can open at a time.
An alert is a critical level Notification. The purpose of an alert is inform the user about something critical, and requires immediate action by the user to maintain quality of experience.
Apps are required to have a metadata file before they can be packaged. This metadata is stored in a file called appinfo.json. The file is used by webOS TV to determine information such as the app name, its icon and other information that is needed to launch and run the app. This file is located in an app's root directory and contains a single JSON object.