Example? I used to work at a company that made femtocells, basically small 3g base stations. All 2 way radios are a co-operative medium, i.e. shouting 'fire' in a crowded room raises the noise floor for everybody so they all need to shout.
We had hundreds of handsets for testing so knew when a particular model/brand/firmware version wasn't working to spec. We'd shoot an email to the manufacturer to get it sorted. Most were fine, but the one that never responded? A certain fruit related company.
Probably the fruit company with the most models of phone (Nearly all white label Huawei models, but still!)
I don't think my operator even knows what kind of phone I have, let alone any access to any software on it. How could they be controlling it? Is it something actually in the SIM?
> To isolate the cellular modem from the SoC, we will be placing the modem on the (remarkably fast) USB bus and have the phone interact with the cellular modem through USB instead of on the main RAM bus. This will separate the cellular modem on its own bus without seeing any other data.
It's a little different than it used to be though. Historically, the carriers require their magic signal bar algorithms/network type display by contract if you wanted to sell phones in their stores.
Now, less phones target each carrier specifically than used to, but ...
Some of them also used to require display of various network types in various situations (IE you were required to display 4G in circumstances where it was on their "4g network", regardless of whether you were using a 4g protocol)