With the debut of Apple's new iPhone, the major wireless carriers are battling it out to entice new customers with the best trade-in deals. Jenifer Robertson, EVP & General Manager of Mobility at AT&T, discusses what the new iPhone means for AT&T and how the carrier was the first to lean into an aggressive 5G device strategy. She also talks about AT&T's move to ditch its WarnerMedia operations and return to its roots as a phone company.