Some time ago there were jokes about free phone plans where your calls would be interrupted by spoken ads. It turns out the ad-supported revenue model did come to phones after all, but in the form of free apps with banner ads. That's the one thing I don't like about Android, but I can understand it. Apps are free. That's pretty much what we do these days. But someone has to get paid, and that means either a limited app demo plus a paid full version or ads (plus possibly paid ad-free version). I think this model is here to stay, at least for a while.
Mokalus of Borg
PS - It's not exactly like the old jokes.
PPS - But the point is that ads are supporting our phones, to an extent.