My question is: I’m running a C8, updated to latest version. All of my water sensors are grouped with life safety sensors in a room called “security,” but the only thing that shows in the new app when I look at devices by room is my Aeotec siren. Smoke detectors, CO detectors, and water detectors are all missing.
That said, I can add them to dashboards.
Is there a fix for this or something I’m doing wrong?
You didn't say if you're using the iOS or Android app - appears to be iOS but not 100% sure as I haven't seen the new app on a tablet.
Regarding your question, the previous version of the mobile apps, along w/the new versions, do not display leak sensors on the Devices tab. You can, as you've noted see them in a dashboard in the mobile app. The Devices tab has been focused on bulbs, switches/dimmers, and plugs, things you may need to turn on/off, set dim level.
So not a bug, it's the current design of the apps. That might change in the future but for now no leak sensors on the Device tab.
There is a Mobile Apps category where you can post questions/comments about the mobile apps - more likely to be seen by the appropriate HE personnel in that category.