Suppose I lost my phone and I could use find my phone to find it. The problem is I don’t have my phone in order to find my phone with. I don’t have a computer I don’t have a laptop All I have is a phone. How on earth would I use find my phone to find my phone?
It all starts with a dating app - find the person of your dreams, build a life together, have children, help them grow up, then …… you have a house full of people with phones who can find your phone!
But more seriously: assuming Apple, I can find my phone from my iPad and from my Watch. I do also have the family set up as an iCloud family so that is easy as well. I expect any Siri device as well