Three things a custom ROM can't change about your phone, however hard you harden it.
The IMEI. It's burned into the modem at the factory. Every tower you connect to logs it, and it's still the same after a wipe, a new SIM, and a new OS.
The baseband. A separate computer with its own firmware. GrapheneOS keeps the OS away from it as far as the hardware allows, but it doesn't run it and can't audit it. Nobody outside the chip vendor really can.
The line. Whatever name is on the SIM is who the carrier thinks you are, and no ROM touches that. If the SIM has your passport attached, you hardened the phone and left the network side wide open.
PikaSim
npub1vt…fnulm
2026-10-06 21:33:19 UTC
Author Public Key
npub1vtwqkw59q7heudskvx9g92d8wrvc0lj8a2qe34ul6x7hc3vpxy4qzfnulmSeen on
wss://relay.damus.ioPublished at
2026-10-06 21:33:19 UTCEvent JSON
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"content": "Three things a custom ROM can't change about your phone, however hard you harden it.\n\nThe IMEI. It's burned into the modem at the factory. Every tower you connect to logs it, and it's still the same after a wipe, a new SIM, and a new OS.\n\nThe baseband. A separate computer with its own firmware. GrapheneOS keeps the OS away from it as far as the hardware allows, but it doesn't run it and can't audit it. Nobody outside the chip vendor really can.\n\nThe line. Whatever name is on the SIM is who the carrier thinks you are, and no ROM touches that. If the SIM has your passport attached, you hardened the phone and left the network side wide open.",
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}