iOS 18.4 update introduces the option to open favorite chat in Messages from the lock screen for quick access.Setting up the chat shortcut through the Shortcuts app is simple and allows for customization of lock screen shortcuts.Users can add multiple chat shortcuts to the lock screen for easy access, along with other customization options in iOS 18.4.Additionally, users can prioritize important chats in messaging apps like Apple Messages and WhatsApp, enhancing message accessibility.