In the past the issues I’ve had with mobile presence were related to it not detecting when I had entered or left the geofence. I just got a new phone, and last nite ran into a new issue. Even though my phone was sitting 2 feet away from me the entire nite, Smartthings decided that it saw it leave and return a few minutes later several times. When it left it armed my system, with predictable consequences since I have motion sensors all over the house. I’m lucky that I don’t have a garage doors or locks connected to the “arrived home” action or else my whole house would have been unlocking itself in the middle of the night!
From past discussions I’ve read on the forum it seems like some phones work better than others for the geofence. I never saw this issue in many months of use with my previous device but hit it the first nite with the new one (a Moto X). This was not due to a collision between devices, my old phone is now permanently powered down.
So what I’d like to suggest is an improvement. Most people using Smartthings are going to have WiFi systems, properly secured with passwords. The improvement is to have the mobile presence app associated with a phone “or” together the condition of being inside the geofence as reported by the Android system with a condition of connected to the home WiFi. This way even if a flaky geofence notification is seen that the phone left it won’t cause any changes, under the reasoning that if the home WiFi is still connected the phone has not left.