If you’re selling your iPhone or giving it to someone, you’ll want to remove apple id from it. Here’s how to do it!
Checkout this video:
Open settings app on your iPhone.
Open settings app on your iPhone. Scroll down and tap “iCloud.” Scroll down and tap “Delete Account.” (This will only delete the account from your iPhone, not from Apple’s servers.) You will be asked to confirm that you want to delete the account; tap “Delete” to confirm.