I would like to support my announcements of iPhone applications in Apple Watch from the very first moment of the Watch release
Yes, notifications for your iOS app will work from day one on Apple Watch.
Do Watch Watch notifications have action buttons similar to those configured for the iPhone app?
If your iOS application already supports valid notifications, they will work with Apple Watch.
Is there a way to verify that the simulator can verify that it is working as expected?
The good question actually is, you cannot test your current iOS app notifications running on the simulator, but you can test the notification user interface from WatchKit.
You must specify a function request for this.
Is there a way to support only notifications without creating a Watch app?
No, you need to provide a Notification JSON payload sample as part of the WatchKit package for which you want to send the Apple Watch application.
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