You could if you don’t need to use the Alexa or IFTTT integrations since they ST supports a 1:1 relationship with them.
The other problem with using a single account is that there is just a single member with multiple presence devices. It can be tricky to write Routines because of the inflexibility of ST app interface.
Not sure I follow… Could you share an example?
I don’t have it set up that way right now, but from what I remember you only get the option of “All Phones and Tablets” or “Any Phones or Tablets” are at/away from a location. So, you can’t really write Routines where you have “If Person 1 is home but Person 2 is away from home”.
You should be able to proxy presence with a virtual switch and do it that way. It would take several routines, though.
If person A is away, turn on virtual switch A.
If person B is away, turn on virtual switch B.
If virtual switch A is on and person B is home…
Etc.
You could also use a physical device as a proxy, like one socket of a power strip, if you don’t want to use virtual devices.
So doable, just clunky. 
You’re saying this is doable with 2 phones running the ST app with the same credentials? Just want to make sure I understand correctly.
…and if so, do you have any other advice against moving from using separate ST app login credentials, to using the same on both?
Same user ID on two phones? No, I don’t think that works. But admin user on one phone and guest user on the other should. 
I probably misheard the original question. My bad.
Yes, that’s how I used to have it set up when I initially started with ST. Two phones logged in as the same ST user. As I said, you will have one member (the account owner) with multiple presence sensors representing each phone that is sharing location. And as I said, it’s cumbersome and tricky managing Routines with the built-in Member Location triggers using that model.
As @JDRoberts suggested, it’s more manageable if you use virtual presence sensors in Routines since you can include multiple presence sensors as the triggers or preconditions in a Routine (see below). If you are going to use ST location to track you, you then need to have Routines that change the virtual presence sensors based on the specific sensor listed for the member in the Member location triggers; i.e. “If Member Dave Dave’s phone presence sensor is present, set virtual Dave presence sensor to present” and “If Member Dave Wife’s phone presence sensor is present, set virtual Wife presence sensor to present”. And of course you need the opposite for when you’re not present.
The plus side of using virtual presence sensors in your Routines is that you can change the underlying tracking mechanism and only have to touch the 4 Routines that set the virtual presence sensor state.
I will just throw in here that, if you have the Alexa app on your phones already, you get a lot more flexibility using Alexa to sense presence.
SmartThings has one geolocation place and radius.
You can create multiple Alexa routines on each phone that each trigger at a different geolocation boundary. Alexa can trigger a SmartThings Scene or change the state on one or more devices.
cool. Thanks yall!
Is there a [vEdge] for virtual presence recommended to use?
EDIT: I see vEdge Creator v2.8…
That’s the one I prefer.
So I have virtual presence sensors defined, and their value set by the ST phone:
So the virtual presence sensors will change to whatever the ST phone presence sensors are.
Presence on her phone seems to work for like the first day, but then quits working.
It doesn’t do anything about the lack of reliability of the ST app’s location service. We were addressing your question about whether you can use a single ST account on both your phones, and if so, how to do that.
As I said in previous posts, I’ve never found ST location to be reliable which is why I used Life360 until it was discontinued in Jan. Gave ST app location another try but it was unreliable on both our phones (Android and iOS) so went a different direction with Alexa app location. At this point, I’d say that your options other than ST are the ones discussed in @JDRoberts earlier post.
I had similar issues plus a serious problem with Smartthings accidentally deleting my entire account. I have since transitioned to the Hubitat hub and I am extremely happy. All the issues I had with Smartthiings are gone. Presence sensors work, Life 360 is integrated, IFTTT works, and programming is much more capable. Customer service is great and intelligent. Plus all is backed up automatically and routines run locally.
Look at the Hubitat hub as an alternative. Much more versatile!
so… I’ve had this in place for almost a month, and it works fairly well.
It works reliably on my phone.
On my wife’s phone it’s less reliable. there have been IDK a half dozen times that she comes home and the Alexa routine doesn’t execute.
Life360 notifies she’s home; SmartThings even shows her phone’s location is at home. (Although that’s another whole reliability issue…)
Anyway, if I run the Alexa routine on her phone (that detects her presence at home and set an Edge virtual switch), it does trigger correctly. So, I’m a little confused as to why the Alexa sometimes does not execute automatically (but will get the correct result when executed manually.)
Suggestions?
It’s interesting. It works flawlessly when we’re at our house in CA. Occasionally at our house in GA, it fails to recognize we’ve arrived in time to unlock the door, but I have a very tight geofence and I’m not sure the cell service is as dense as it is in CA.
Also, iPhone seems to be less reliable than Android.
I too struggle with ST presence sensing. My Wife’s & I’s Galaxy phones are very consistant, but 2 other LG Phones in our house are about 50/50. Since I don’t us Alexa for voice control or anything else (Google Home Guy here), I have simply created 4 of @TAustin Virtual Presence Sensors and created Routines for each of them to respond to ST presence changes. I then changed all my other Routines that are requiring presence to look at the virtual devices instead. If ST catches somesbody coming or going it will change the Virtual Presence Sensor accordingly, and if ST things does not catch the coming or going, @TAustin Virtual Presence Sensors allow me to manually trigger home or away for each of us. This way between ST presence and me being aware, I can keep all my presence dependant Routines functioning fine.
I have it set up similarly for my presence dependent Routines, but just using Alexa as the underlying detection mechanism. The plus side to doing it this way is that you can always change out the underlying detection mechanism by touching just two Routines for each location member and never having to change your Routines that perform presence related activities.
Truth!
I was tired of changing Routines just so that Routines would trigger after ST presence missed somebodies coming or going.
Thanks yall!
I made 2 vEdge presence virtual switches for each phone:
Alexa ROUTINES:
Dave Depart Home
Dave Arrive Home
SharpTools RULES:
If Any “Dave’s (Alexa) Presence vEdge”, 'Dave’s s23 (phone)" CHANGES to ‘Present’ THEN “Dave’s (ST) Presence vEdge” = ON
If Any “Dave’s (Alexa) Presence vEdge”, 'Dave’s s23 (phone)" CHANGES to ‘Not Present’ THEN “Dave’s (ST) Presence vEdge” = OFF
I then use the “Dave’s (ST) Presence vEdge” virtual switch to determine if I’m actually home. Appears to be working.
Is this similar to what you all are doing?
Thanks for the suggestions, everyone!
