By Brian X. Chen, The New York Times Company SAN FRANCISCO — Apple introduced a pop-up window for iPhones in April that asks people for their permission to be tracked by different apps. Google recently outlined plans to disable a tracking technology in its Chrome web browser. And Facebook said last month that hundreds of its engineers were working on a new method of showing ads without relying on people’s personal data. The developments may seem like technical tinkering, but they were connected to something bigger: an intensifying battle over the future of the internet.