@baivab Yes. You can still pair and it still works interconnected with other smoke detectors.
You must use the smart things classic app to do the intial pair. You also need to hold the center button on the smoke detector for 20 seconds to factory reset it. After you pair it you need to manually refresh it or temp and humidity will never show up. But after refreshing once they show up.
In the smart things classic app you still have full capability to turn on and off the weather channels (doesn’t show up in new app) the new smart things app can control. The new app and has full control over brightness and color. But cannot hush.
As far as I can tell I am unable to easily trigger an alert when an interconnected detector is detected. I am sure it’s possible but needs some more in depth programming then just ifttt. I can see halo detected the event via smart things classic of “interconnected detector detected” but not sure how to pass this to smart things automation or ifttt