I am thinking of creating an app that only allows users connected via a cell tower. Are there IP ranges that are only used by cell towers?
I realize that it may be a 'moving target', but does anyone know of a list of the current blocks (like black lists for spammers).
I do not want to rely on headers as they can be spoofed. IP address seems to be the only true way of identifying the client is on a cell network via IP.