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by nik282000 136 days ago
Factory reset an old phone and leave it in airplane mode.

If it get "lost" or "stolen" you aren't out much, and it doesn't contain any personal information. If "law enforcement" gets their hands on it the only data it has is the IMEI and maybe wireless MACs, enough to ID you based on previous use but they would have to contact telecos and request the info. Current "law enforcement" seems too chaotic to spend time tracing the owner of an empty phone.
2 comments
diogenes_atx 136 days ago
For a detailed discussion about phones, personal data and anonymity, there is a good book written by a former police officer: Michael Bazzell (2024) Extreme Privacy: What It Takes To Disappear, fifth edition.

https://www.amazon.com/Extreme-Privacy-What-Takes-Disappear/...

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thomascgalvin 136 days ago
I'm not an expert in digital footprint-hiding, but it's probably a good idea to replace / remove the SIM card as well. A factory reset will leave data laying around, just not accessible through "normal" means.
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palmotea 136 days ago
Or just buy a cheap point-and-shoot, and stick a giant SD card in it:

https://www.bestbuy.com/site/searchpage.jsp?browsedCategory=...

That's seems like an all-around better option than trying to make an old phone work like a point-and-shoot camera.

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Krutonium 136 days ago
On any modern phone, your phones user partition is encrypted with a key that is itself encrypted by a key stored in the CPU. When you factory reset, what's happening is basically the key in the CPU is deleted, then re-created. At that point the data on your partition is random noise, so a new encryption key is derived and used to format the partition.

Even better, modern Android then encrypted your personal data with yet another layer based on your password/key/pattern you use to unlock your device. Many layers.

Retrieving that data would be incredibly hard even for a nation state unless the encryption used was deliberately backdoored, and even then once the device TRIM's the space (which it likely does prior to formatting) that data is gone on a hardware level.

(TL;DR Can't move the memory chip to a new device, and even if you backdoor the OS you still need the users password)

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