Hi,
i have a major problem in app notification settings. i have multiple devices and every month i change my mobile. due to this i have to go to modify the rule and select the device every time. is there any way if i login in any device i receive the notifications with out modifying the rules.
like smarthings if i select notify me. no matter which moblie im logged in it gives me notifications
Hubitat and SmartThings notifications work differently; with SmartThings, it's tied to your account and will notify an app/device logged into that account. With Hubitat, notifications go to a device, so they're just like regular device commands (e.g., turning on a switch, where you have to select a device to turn on). But, when you log into the Hubitat mobile app on a new device, you should be prompted whether you want to create a new mobile app device or re-use an existing mobile app device. If one device is replacing the other, it sounds like you might want to use the second option instead of the first--then, the existing device will be associated with your new app/device, and you won't need to swap anything out.
If you do want to create a new device on Hubitat for some reason, then there is at least something that can help you without needing to manually swap it in all apps/rules: the Settings > Swap Apps Device feature, added in platform 2.3.1.
I also have a custom app/driver that can be used to group or "proxy" notifications through a virtual device, then you'd only need to swap it out in that one app and will affect all, but with both of the above, I'm not sure you'd really need that.
You might be better off using Pushover. At least you won't have to change anything more than once each time that way
if i select the existing device name, instead of creating new device during log in will the appear on new mobile?
I think there's a typo in that post, so I'm not exactly sure what you're asking, but if you mean "they" instead of "the" and by "they" you mean "notifications," then yes. And it doesn't just apply to notifications, since the mobile app device on the hub can do both notifications and geopresence (though neither needs to be used), and all functions will be taken over by the "new" phone/tablet if you choose to re-use the existing device on the hub.
Just to reiterate what @bertabcd1234 already said. The mobile device on your hub doesn't change if you replace the phone. When you log in the mobile app from the new phone, be sure to select the existing device that was previously created and the hub makes the connection with your new phone. No need to do anything else. Any rules you have, will continue to work for the new phone using existing device on your hub.
Got it thanks.
Come back and let me know if it worked, cos it never did for me.
I am not changing my phone every month like the OP, but certainly I am changing my phone at least twice a year and can tell you that it has worked for me at least 8 times (2 of which flipping between Android and iOS) 
It was the same phone all the way through. I noticed after weeks when I didn't get a notification I should have got, and it turned out it had made me a new phone when I opened the mobile app (which I do very rarely) So I got more careful and made sure to choose the existing phone device it offered and it still made me a new phone. My husband tried it and the same thing happened to him. This was some time ago and it's stopped happening now. Maybe there was some weird glitch just happening at the time.
Download the Hubitat app
