Better practice is not presuming that you can predict every possible use case. For example, concurrently testing existing and new virtual presence sensor drivers.
I suppose the single output reduces the complexity of the code and I can just created another Combiner instance.
If you don’t like the way it works, feel free to write your own app.
If you want multiple output sensors you can just make a simple automation or RM to mirror to the new virtual sensors.
I absolutely 100% have not predicted every possible use case. I wrote the app for my use case, and shared it out for free. Some people have also found it useful for their own use cases. That's all that has happened here.
Interestingly, this article popped up in my feed this morning: Making is Show Business now – alexdanco.com
Super interesting. It talks about how with open-source software, there's a cost to having users or contributors or "fans". Getting a pull request from someone who wants to help is great, but it's not free work. The creator/maintainer still has to review it, decide if they want it as a feature, decide if it matches their coding style and architectural choices, figure out if it has bugs, and incorporate it and then maintain it going forward.
I haven't had a lot of pull requests from users for my Hubitat apps/drivers, but I have had a few. And I'm thankful for them. But I can for sure see how if there were a ton of them, I wouldn't have enough time for it.
For the same reason, I try to be pretty careful @-mentioning the Hubitat staff, like bcopeland. They have limited time, and while I have sent them bug reports and suggestions, and they've been gracious and run with some of them, I don't want to take their time unless it's really important.
Or even better, because this is released under a permissive open source license (Apache License 2.0), you are free to take this app and modify it to meet your own needs. You can build more using it as a base. The only restriction is that if you distribute yours, you must do so under the same license.
Absolutely! 
So this happens even if you don't have a weird setup. I have two standard combiners, one for me and my wife, and one boolean combiner to determine home presence.
I am working from home today because I have a cold. My wife just left the house and this is what happened.
And my rule that triggers on arrival fired.
And then this just happened. I was messing with my wifi and noticed that it was triggering arrivals for the standard combiner every time my phone connects or disconnects from wifi. Because I'm inside the geofence, the presence never actually departed, so it shouldn't be reporting an arrival.
I think maybe part of the problem is what I highlighted. Right now, my phone has wifi turned off and is not on the network, but I am at home. So one presence sensor is saying present and one is saying not present. That last "Presence - Scott has arrived" message was from my phone disconnecting from the wifi.
Can you send screenshots of the configuration pages for your combiners?
Sure, but I have it setup pretty standard. Wifi presence is using the iPhone wifi presence sensor driver and the GPS position is just the Hubitat app.
Were there any other events between these two?
No. It happened between when I was turning off logging for a button and checking for updates in HPM. That's how I noticed it actually.
One thing that is weird though is that the exact time stamp I see now is different than it was before. I mean, it's only off by .025 seconds and .002 seconds, which is practically nothing... but why does it show different for me now?
That IS odd.
i am having alot of trouble traying to understand how it works and i am sorry. but is there an easier guide on this?
i need to have a presence on my wife and mine iphone.... but using wifi. to avoid gps because of battery etc... i have the regular presence setup but sometimes we are home and wifi on iphone sleeps and marks us like away... so i was recommend to try this to have several checks before or something like that.
thanks in advance and be patient with this new hubitat user and willing to learn
There are a couple things you can do to make it more reliable. In the wifi connection settings there is a setting that randomizes your mac. Turn that off for your home wifi. Secondly, turning off the battery saving feature. Or at least setup a quick setting to turn it off when you're home since you can easily plug it in when needed.
Third, add a device other than your phone to the mix. A bluetooth dongle, pressure mats connected to contact sensors, etc... Maybe even a TV when on means you're home.
Finally, use presence for specific events and limit the time windows that they will trigger. This will prevent false positives. Coming home from work when you typically get home around the same time.
That's interesting. It would be awesome if Hubitat's own app presence were more reliable for me.
I tried it yesterday and it’s unreliable.
I’m sicking to Apple HomeKit, it’s as close to perfect as it gets.
I'm still having weird issues with the combined presence. Nothing has changed from the screenshots I posted above. Currently, both GPS and WiFi are showing as not present, but the standard combiner for me is still showing present.
Download the Hubitat app
