Don't forget that...
Don't forget that there is other software in a phone besides the obvious OS and apps.
Just for example, the actual transceiver or "baseband" chip will have it's own software load, quite separate from the OS. And the power control IC probably has a SW load. Even a SIM card is actually a computer.
I'm waiting for the day when someone will start selling a single PN of SMT resistor that can be programmed, perhaps over NFC, to any value of resistance. When that day comes it would help people to not forget hat there are other software items in a phone besides the obvious OS and apps.