The SIM card is a separate OS that gets underneath the SOC's OS. It can run its own applets without the knowledge or permission of the SOC OS. https://www.you

The SIM card is a separate OS that gets underneath the SOC's OS. It can run its own applets without the knowledge or permission of the SOC OS. https://www.youtube.com/watch?v=31D94QOo2gY https://www.youtube.com/watch?v=31D94QOo2gY The baseband is a completely different RTOS as well. And then there's also TrustZone running in the SOC as well.