Big discussion on presence in the topic below, but in summary:
ST app based presence on your phone works well for some, but not so good for others
Alexa or IFTTT app presence on your phone can be used to trigger virtual presence sensors in ST which can be used in ST Routines/Rules API
Using virtual presence sensors vs member location in Routines allows you to switch out the underlying presence detection mechanism without having to touch all your Routines
I’m personally using Alexa presence for our household and it has been working reliably for us (and is discussed in that same topic).