Custom application/script: Iterate through WiFi devices, compare, send information to server

[ColinTaylor]

Now I am wondering: is it possible for my router to detect that my phone is in WiFi range, even when the phone hasn't (yet) connected to my WiFi network?

No.

So it turns out that my phone connects to my WiFi network just a little too slow for this system to work as intended.

What is the intended purpose?

 

[birgersp]

Okay. I am looking at some alternatives. Looks like I could be using my RPi as a WiFi-device monitor.

The purpose is to detect (ASAP) when I come home, using my smartphone. Currently the detection is too slow (my phone takes about 10 seconds to connect to my home WiFi when in range).