We have 4 people in our house and each has an Android phone and a Google account. Each family member sets up a Home in the Google Home app, turns on phone based presence sensing in the GH app, (you can have multiple) and links it to SmartThings. Then in ST I have a virtual switch for each person. In the GH app for each individual home they tie the built in Home/Away routine to turning that virtual switch in and off. I then have a few routines in ST looking for various combos of those switches being on and off and executing different things, like setting the STHM setting or locking doors and stuff.