Discarding a phone safely can be done with a minimum of fuss. Here's what you need to do:
Remove any memory cards. If your old phone has a removable memory card slot (typically holding either an SD or Micro SD card), remove the card and keep it. You don't need to include it in the sale of the old phone, and keeping it prevents you from having to securely wipe the data on it.
Remove the SIM card. The SIM card -- which gives your phone its number and identity on the network -- can also store data like contacts and call logs. The buyer has no need for your SIM card, so you should keep this as well. You'll typically need a pin-like tool to pop the SIM card out of its storage slot.
Wipe the phone and return it to factory conditions. This should be common sense, but you absolutely must "wipe" your phone before giving it away. This step makes it factory-fresh and eliminates any trace that you once owned it. There's an easy way to do this built into all major smartphone operating systems today:
- In iOS, choose Settings, General, Reset, Erase All Contents and Settings.
- In Android, it can vary by manufacturer, but you should look in Settings for something like Backup & reset.
- In Windows Phone, go to Settings, About and choose Reset Your Phone.
