If Apple really wanted to put its cash to use, it could build its own cellular network. Privacy focused, no surprise fees, integrated billing for desktop/laptop/iOS/watch devices.
There's enough bad will against the existing ISPs/mobile carriers that Apple could swoop in and gain a lot of market share very quickly. And customers could save money by combining their home internet with their mobile plans. The future is a singular wireless data subscription without any routers or modems.