We're still early days. It'll all be quite seamless.
Even the phone relay setup could just be a button you press in your client, or it could auto-setup, when you install a client. That's probably where Damus and Amethyst will be or are.
Users actually can't differentiate a client from a server, if you make the interface very smooth.
Most people have multiple servers running on every device and don't even notice.
That's what I would hope, but, at a level of efficiency that you really don't notice the network and battery on a phone.