As smartphones become central to everyday life, they accumulate a wide range of data: identity information, contacts, photos and videos, messages, and sometimes even payment details. That’s why **proper data erasure is critical** when you sell, transfer, recycle, or discard a phone.
This guide summarizes practical steps for iPhone and Android, plus important cautions.
How to erase data on iPhone
1) Back up important data
Before erasing, back up what you need:
– iCloud: Settings → iCloud → choose data types → “Back Up Now”
– iTunes (Windows) / Finder (macOS): connect the device and create a backup
2) Erase all content and settings
Settings → General → Transfer or Reset iPhone → Erase All Content and Settings.
This returns the device to factory state.
Important cautions for iPhone erasure
– Turn off “Find My iPhone” before handing the device off.
– Confirm Activation Lock is removed.
– Remove the SIM card if you plan to sell or transfer the device.
How to erase data on Android
1) Back up your data
Back up via your Google account or a PC. (Menu names vary by device; for example, Galaxy devices offer Google One backups.)
2) Sign out of your Google account
Settings → Accounts → Google → select your account → Remove account.
3) Remove SD card (if present)
SD cards may contain photos and videos. Remove them before wiping the phone. If you use mobile wallet features, migrate data as needed.
4) Factory reset
Settings → General management → Reset → Factory data reset (menu names vary).
Android cautions
– Turn off “Find My Device” (Android device finding) when applicable.
– Remove the SIM card before disposal.
Factory reset is not always the same as secure erasure
Even after a reset, some data may remain recoverable under certain conditions. If you need stronger assurance—especially for sensitive data—use dedicated sanitization tools that overwrite or otherwise securely sanitize storage.
When in doubt, consider using professional solutions such as MASAMUNE to help reduce the risk of recoverable remnants.
