I live in a metal sided, metal roofed house so I thought this could be a possibility. If I open Locus Maps on my couch the GPS page will see a few low quality satellites and indicate my horizontal accuracy is ~76m or so. So I increased my geofence size to a 600m radius and still experience this issue.
The geofence page says I'm inside the geofence, the devices page says my phone is not present.
Just happened again a few minutes ago. The logs say my phone has left but they don't show the phone returning yet the app says my phone is still inside the geofence. It has been happening maybe once a week or two. Odd.
One thing I keep trying to remind other users about was an issue I discovered when I had attempted to use a magnetic mount for my phone in the car. We had random issues before that, but it became a 100% everytime I put the phone on the mag mount.
The mag mounts/chargers will instantly screw your compass on your phone. I have a video that I made to send to the manufacturer I was using. While that should not matter with "GPS" the Google API requires a calibrated compass to get your location correct. To test the theory, I calibrated the compass, and it INSTANTLY reported correctly. Then, I realized that the magnetic closure cases we were using were slowly doing the same thing, likely causing the other random issues we were having.
On Android, there is an app, GPS Status & Toolbox. It has a compass calibration feature where you can see the status (Green/Yellow/Red). If you open that function, and it is red, you do the rotate on each axis until you get it back to green. You can also see for yourself in realtime if you put it over or near a magnet how quickly it decalibrates.
That is one potential cause.
Another I found over trial and error is that I had set my radius to a distance that it was either entering or exiting the geofence area just as it was switching from my wifi to cell coverage. I found this by accident when I was also using tasker to switch my combined presence. Tasker was throwing an error (unable to reach the endpoint) until I chnaged the zone. I realized that the HE presence could be suffering the same issue. I increased the geofence on both, and now my Tasker rarely if ever has to kick in to fix my presence. I have it set to speak a message when it does, so I know if it happens. The tasker rule trigger is leaving the geofence area. On trigger, it checks my combined presence device to see if it matches what it should be (present/not present). If HE presence was working, then the combined presence would already match. If HE is wrong, the combined presence will also be wrong, and tasker changes my combined presence and tells me it marked the phone home or away as appropriate.
Those two fixes (quit using magnetic anything around my phones and changing the geofence radius) along with the proper background and battery changes have made my HE presence detection almost perfect rendering my need to keep using tasker more of a comfort/safety/backup than anything else.
Edited to add: These are just observations I found and something to try. I have no idea how iphones use/detect presence and I suspect that they don't have the same issue with magnetic decalibration of the compass since I don't believe they use the google play services for location.
Same issues on multiple different android devices here going back about 6 months. I've just given up on Hubitat's android app, it's not maintained, at least on anything more than a couple devices it seems.
Download the Hubitat app
