If it's hardware controlled, then the Graphene OS team would have to find a flaw in the hardware, or trust that when they tell the hardware to shut off, that it really does shut off, or find a way to verify that the hardware is really of. But even if they could tell the hardware to shut off, verify that it's off, and then shut down, the hardware could turn back on after the software is off and the software would be none the wiser.
The only way 2 ways anybody can be relatively sure this feature is off are:
- pulling the battery:
- good luck with that with phones that don't have removable batteries
- hopefully there won't be a small backup battery to power this specific circuit
- physically disconnecting this circuit from other circuits:
- that might mean saying goodbye to bluetooth functionality on the phone
The alternative is getting a linux phone with hardware that doesn't have this feature.
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