As stated! This might be discussed somewhere already, but I can't find anything when searching.
One thing I really miss from SmartThings is warnings for low battery and (in theory) offline devices, although the last one is/was pretty broken. I guess some kind of low battery support might be implemented in the upcoming mobile app, but until then - is there a good monitoring solution out there?
I use the Hubitat Safety Monitor App (Custom Monitor Option) to monitor battery status dropping below x%) seems to work well for me. Monitoring device "health" is a different challenge since it relies on the device reporting status on a predictable basis which isn't the case for most "battery" devices due to power management. I do believe it is a "feature" that is being worked on by the Hubitat team though.
Yeah, I realize it's a challange, and it really doesn't work that well on ST either. I guess it would be nice to have the ability to fine tune on device level, as some checks in more often then others. Things marked as INACTIVE now can be both due to not used in a while but still connected, or actually lost from the network.
I personally use a WebCoRE piston for this as I can tailor it for various devices.
For example, the developer of the drivers for xiaomi devices was nice enough to include a last check in variable. So for those devices I can monitor that and if they stop checking in after X hours send a notification.
Other devices I'll check check if they go Inactive which I believe happens after 24 hours of no activity. But the problem is that things like my zwave dining room light that doesn't get much activity will go inactive so I set up the script to just send it a ping/poll/refresh if its inactive just to force it to report in.
This all seems fairly useless to me given how many devices I have with dead batteries, which are nontheless reporting 100% battery. Especially a problem with contact sensors it seems.