> As other have said, iPhones have an external modem and are fine. Qualcomm insisted on this because they had it, and they're good at marketing.
Addressing the second sentence - I have no knowledge of what transpired but my assumption would be a combination of Apple didn't want to have their SOC's fab'd by Qualcomm for the sake of an integrated modem, and Qualcomm didn't want TSMC fab'ing their modem IP into Apple's SOC's, so the obvious solution was a discrete modem which was a product they could offer.
The wording makes it extremely unclear. Both Company don't "Fab" those SoC. What you are suggesting is Qualcomm doesn't want to give the IP to Apple for Modem SoC Integration, and Apple doesn't want to give their IP to Qualcomm's SoC designed specially for Apple.
While those point are valid they are not the reason Apple have a separate Modem Chip. The design of iPhone had the Modem literally in a completely isolated system, and act more like a USB modem directly connected to the Internal iPhone for security purposes.
And as other have mentioned the integrated of Modem within the SoC have minimal impact to overall battery life.
Addressing the second sentence - I have no knowledge of what transpired but my assumption would be a combination of Apple didn't want to have their SOC's fab'd by Qualcomm for the sake of an integrated modem, and Qualcomm didn't want TSMC fab'ing their modem IP into Apple's SOC's, so the obvious solution was a discrete modem which was a product they could offer.