A phone gets sold, a laptop is handed to a relative, an old tablet goes in for trade-in. Before that, people usually delete their photographs and sign out of a couple of apps, and consider the job done. It is not.
What stays on the device
- Passwords saved in the browser and a signed-in mailbox, if you never signed out.
- Authenticator keys — and with them, your second factor.
- The link to the manufacturer's account. The device stays registered to you, and the new owner cannot activate it.
- The Wi-Fi password and every network you ever connected to.
- App data — conversations, documents, cached maps.
- The memory card and the SIM, which are what people forget most often.
The order for a phone
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Move the second factor
Before anything else. A reset destroys the authenticator's keys with no way to recover them — the migration in detail.
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Make a backup
And check that it opens. A backup nobody has checked is not a backup.
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Sign out of the manufacturer's account
Sign out specifically, not merely reset: otherwise the device stays linked and the new owner cannot use it.
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Sign out of messengers and banking
Signing out ends the session on the service's side; a reset does not.
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A full factory reset
Not deleting apps by hand. On modern phones the data is encrypted and a reset destroys the encryption key — that is enough.
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Remove the SIM and the memory card
A phone reset does not touch them.
The order for a computer
| What | Why | How |
|---|---|---|
| Deactivate licences | Software binds to the device and activations are limited | Deactivate inside the programs before resetting |
| Sign out of accounts | Sessions stay active on the services' side | Sign out manually, then end sessions in the account settings |
| Check the second disk | A system reset does not touch additional drives | Format it separately |
| Confirm the disk was encrypted | On an unencrypted disk the data is recoverable | If it was not, overwrite the disk completely |
| Reinstall the system | More reliable than deleting an account | A clean install with formatting |
After handing it over
If a device is lost rather than sold, the order is different and starts with blocking — that is covered in security while travelling.