# GroupSessionMessenger An object that transfers app-specific data between the devices joined in a group session. ``` final class GroupSessionMessenger ``` ## Overview Use a `GroupSessionMessenger` object to coordinate your app’s behavior across the devices attached to a group session. This object leverages the existing FaceTime communication channel to send app-specific data related to a SharePlay experience. For example, a movie-watching app might share user comments or tags while the movie plays. You create a `GroupSessionMessenger` object directly and use it to send and receive app data. Create the messenger using an active [`GroupSession`](/documentation/GroupActivities/GroupSession) object, which manages the underlying communication channel. Store a strong reference to your `GroupSessionMessenger` object for the lifetime of the session. The following example shows a custom object for managing a movie-watching experience. The object stores the GroupSession object associated with the experience and creates a `GroupSessionMessenger` for sending messages between participants. ``` class CowatchingExperience : ObservableObject { let groupSession: GroupSession let messenger: GroupSessionMessenger init(groupSession: GroupSession, item: Trailer) { self.groupSession = groupSession self.messenger = GroupSessionMessenger(session: groupSession) self.groupSession.join() // … } } ``` For more information about establishing a group session, see [`GroupSession`](/documentation/GroupActivities/GroupSession). ### Receive Messages from Other Devices The system delivers messages to your app asynchronously when they arrive and adds them to a message sequence. Use the [`messages(of:)`](/documentation/GroupActivities/GroupSessionMessenger/messages(of:)-626qo) or [`messages(of:)`](/documentation/GroupActivities/GroupSessionMessenger/messages(of:)-jvoz) method to retrieve the sequence you want and iterate over its results. Use a `for`-`in` loop with the `await` keyword to iterate asynchronously over the results. The following example shows how a Tic Tac Toe game might retrieve moves sent by the current opponent. After receiving each move, the code adds that move to the current participant’s board. ``` let sessionMessenger = GroupSessionMessenger(session: groupSession) async { for await move in sessionMessenger.messages(of: TicTacToe.Move.self) { self.board.addMove(move) } } ``` ## Topics ### Creating a group session messenger [`init(session:)`](/documentation/GroupActivities/GroupSessionMessenger/init(session:)) Creates a new group session messenger with [`GroupSessionMessenger.DeliveryMode.reliable`](/documentation/GroupActivities/GroupSessionMessenger/DeliveryMode-swift.enum/reliable) delivery mode and associates it with the specified session object. ### Sending data to the group [`send(_:to:)`](/documentation/GroupActivities/GroupSessionMessenger/send(_:to:)-4o52m) Sends a standard data object asynchronously to other participants in the group session. [`send(_:to:)`](/documentation/GroupActivities/GroupSessionMessenger/send(_:to:)-2a4ku) Sends a custom type asynchronously to other participants in the group session. [`send(_:to:completion:)`](/documentation/GroupActivities/GroupSessionMessenger/send(_:to:completion:)-zufl) Sends a standard data object to other participants in the group session. [`send(_:to:completion:)`](/documentation/GroupActivities/GroupSessionMessenger/send(_:to:completion:)-9e0sn) Sends a custom type to other participants in the group session. [`Participants`](/documentation/GroupActivities/Participants) The set of participants to include in messages. ### Receiving data from other participants [`messages(of:)`](/documentation/GroupActivities/GroupSessionMessenger/messages(of:)-626qo) Returns the asynchronous sequence of messages that contain a generic data object. [`messages(of:)`](/documentation/GroupActivities/GroupSessionMessenger/messages(of:)-jvoz) Returns the asynchronous sequence of messages that match the app-specific type. [`GroupSessionMessenger.Messages`](/documentation/GroupActivities/GroupSessionMessenger/Messages) An asynchronous sequence of messages sent to the session. [`GroupSessionMessenger.MessageContext`](/documentation/GroupActivities/GroupSessionMessenger/MessageContext) A structure that contains additional information about an incoming message, such as which device sent it. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)