I would like to just do a mobile web app test. My idea is to find out if two or more devices are in proximity of each other.
Im thinking this can be done by connecting the web app to a server, which then knows the phones ip and adds it's coordinates in a database. Then if another phone is connected to the app it finds all other coordinates and returns to you the ones that are like 5 km away or how ever many km.
I don't want to use bluetooth either, so any ofther suggestions are welcome. Im am just wondering if that's a good way to go, or at least test.