Apple use a separate modem chip. iPhone12 has a Qualcomm SDR865 baseband and SDX55M radio. There have been rumours about Apple making their own modem, and presu

Apple use a separate modem chip. iPhone12 has a Qualcomm SDR865 baseband and SDX55M radio. There have been rumours about Apple making their own modem, and presumably integrate it in an A-series SoC, but nothing yet. A 5G modem is pretty complicated tech. I used to work on Nvidia's Icera, but that's gone now. A lot of chip makers have given up, and Qualcomm is the undisputed leader. MediaTek dominates in low-mid end Androids. I think Huawei & Samsung both have something.