We Wipe It Anyway, But...
When you donate a phone to us we sanitise it to NIST SP 800-88 regardless. But we completely understand wanting to do a clean yourself first — especially if you are posting it.
iPhone
- Go to Settings → General → Transfer or Reset iPhone → Erase All Content and Settings
- Sign out of iCloud first (Settings → your name → Sign Out)
- Remove your SIM card
Android
- Go to Settings → System → Reset → Factory Data Reset
- Sign out of your Google account first
- Remove your SIM and SD card
Important Note
A factory reset on a phone is more effective than on a laptop, because modern phones encrypt by default and the reset destroys the key. We still run our own sanitisation on everything regardless, so you are covered twice.