Dear fellow plebs and freedom tech lovers
Is my wifi only grapheneOS pixel more or less secure than my mini PC running Linux for the purpose of signing a PSBT transaction for my coldcard?
Discussion
Signing on any device that connects to the internet is insecure. Leave those devices for broadcasting the completed transaction you want shared. Only sign on a device that will never connect to any other device, e.g., coldcard, tails os bootable usb with disabled network communication. As for the broadcasting privacy. I don't have an answer which is better. never used grapheneOS. But it's a general rule of thumb that mobile devices will generally be less private.
> But it's a general rule of thumb that mobile devices will generally be less private.
I disagree with this claim. in desktop OS usually all programs run in the user's context, hence they can access each other's data without much effort, unless the other program prompts the user for a password each time. in Android different apps are isolated from each other's user data. any windows malware can steal your wallet.dat. not so in Android.
of course the system itself has the required privileges, and privilege escalation is s thing. but there are also good reasons to prefer mobile from a security perspective.
if both are only used for the described purpose and physical security is out of scope I'd say both are very secure and would trust quite some value to them. for life changing amounts I'd always opt for completely offline.
also, depending on a lot of factors like FDE, key storage etc data might be easier to exfiltrate from a standard PC, but depending on the bounty that is meaningless.
A phone can never be as safe as a Linux computer.
I'd say your PC. Even with a pro-freedom OS on your phone, it still has internal aspects that make it less than ideal for privacy. A laptop or PC running one of the more popular/vetted distros would inherently be more private.
As for security alone, it's probably about the same for both, except a desktop PC is harder to steal if someone breaks in.