I currently have a tile tracker and GPS logger for the phone.
I am trying to determine a way to create the following alert:
if the coordinates of the tile tracker and the coordinates of the phone are .5 miles apart or greater, then send an alert.

Is it possible to create a zone that dynamical updates the coordinates of the tile tracker? If not then the next option I can think of would be a template variable the calculates the distance between the two devices and based off that distance it would give an alert.

I use the google travel time as well. I also have a binary sensor that turns on if the distance between two points does not equal a set number (Meaning that the path it is taking is different from usual)

The value_template takes the distance attribute, converts it to miles, rounds it to 1 decimal and then compares it to see if it equals 23.5. If so, it turns the binary sensor off, otherwise it is on.

I used your idea to make the following:
itemdistanceproximity:
value_template: “{{ (states.sensor.itemdistance.attributes.duration.split(’ ')[0] | int) <= 5 }}”

I originally used the distance attribute but because it alternated between ft and mi the values were inconsistent. So i kept duration, now it give a binary value for if the distance is greater than 5 minutes.