Before you sell, give away, or trade in your device, you should first transfer information to your new device, then remove your personal information from your old device.
You shouldn't manually delete your contacts, calendars, reminders, documents, photos, or any other iCloud information while you're signed in to iCloud with your Apple ID. This would delete your content from the iCloud servers and any of your devices signed in to iCloud.
- Open up Settings
- Scroll down and tap “General”
- Scroll down and select “Reset”
- Tap “Erase All Content and Settings”
- You’ll be given a chance here to update your iCloud backup before you go ahead. If you’re not sure that you’ve saved everything you wanted to, this is a good time to do a just-in-case save.
- Confirm that you want to erase your device by tapping “Erase Now.” You’ll be asked to enter your phone’s passcode.
- Okay, this is your last chance to change your mind. Are you sure? Then select “Erase iPhone.”