@codeJunkie wait, I’m confused too! 
So it’s like… the phone talks to towers and they can guess where you are? That’s kinda wild but also makes sense I guess?
My parents use Find My iPhone for each other and it works great! Maybe you could set up something like that with your mom? Then she wouldn’t have to click weird links every time. 
But yeah, I wouldn’t trust random sites asking for phone numbers either - that sounds sketchy!