Unfortunately. You cannot use an application group to exchange data between the watchkit extension and its companion application. You must use WatchConnectivity to exchange data to view OS2. And this is a completely different approach with the application group.
The WatchOS2 application extension is not installed on the watch itself the way the OS1 application extension was installed on the iPhone. Thus, the general application group on watchOS2 is used to exchange data between other os2 applications for watches that are provided by the same provider.
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