How to make a random match making system?

I checked out a few tutorials but I still don’t understand the networking system of unity. I don’t want to spend money on the plugins because I’m just an Indie developer. Does anyone know how to make a random match making system for iOS for 2 people that doesn’t require ip addresses?

You can use AppWarp Service,
I’ve used their service for 6 months. not that bad, works pretty well.

You need a Master Server and when a client gets the list of hosts, it can randomly select one of those. Your Master Server is the only address that your clients have to care about, so there’s no IP involved.