Methodology of the Home Messenger App

• The iCloud technology is used for data sharing and synchronization among multiple devices under the same iTunes account.
• The App stores each device's message in iCloud.
• The App stores metadata of the messages in iCloud. The metadata includes creation time and identities of viewers.
• The App deploys the notification center of iCloud. As a result, changes made to iCloud would notify the App. And the App would then update the message information.
• When a device views a message from another device, the message's viewer metadata would be updated. Therefore the users can track who have viewed their messages.
• When a new message is written, a user would be notified because the App knows that the user has not read the message.