I don't know about phones that use Android but iPhones are safe to trade in once you wipe them.

iPhones are encrypted and the decryption key is saved on the phone itself. Without that key, no data can be retrieved. When you do a factory reset, it deletes that key. If you're worried about data recovery, you can factory reset your phone then set it up again without logging into your account (ie as a new iPhone for someone without any apple account stuff) and then do a second factory reset. At that point, the data would have been encrypted then encrypted again. Someone would have to somehow retrieve the second encryption key that was securely deleted then retrieve the second encryption key that was also securely deleted then use that key to decrypt the data. It's basically impossible.

Can’t you remove the SIM card before trading it in? I think that’s what I did last time.

Just wipe it before you send it back.

Anonymous wrote:

Anonymous wrote:I like to keep mine as data back up. I turn off internet so it doesn't auto update to any accounts when it turns on. Then I have an easily accessible backup storage of all my pictures and everything else should I lose my current phone.

For me, this is more valuable than the small trade in amount.

Huh? So you’re backing up on the phone’s hard drive…that sounds like a disaster waiting to happen.

Why? One new phone with cloud backup plus one old phone as a hard drive backup copy. How is this a disaster? What would you recommend as alternatives?

Anonymous wrote:I like to keep mine as data back up. I turn off internet so it doesn't auto update to any accounts when it turns on. Then I have an easily accessible backup storage of all my pictures and everything else should I lose my current phone.

For me, this is more valuable than the small trade in amount.

Huh? So you’re backing up on the phone’s hard drive…that sounds like a disaster waiting to happen.

Why not just do proper backups in the first place?

I like to keep mine as data back up. I turn off internet so it doesn't auto update to any accounts when it turns on. Then I have an easily accessible backup storage of all my pictures and everything else should I lose my current phone.

For me, this is more valuable than the small trade in amount.

Thanks. My carrier usually copies my data onto new phone. How does old one then get wiped before handing over?

Because they are able to resell the old phones.You wipe your phone clean (erasing all the data), back to factory install before you send. Most data is stored in the cloud these days, so once you remove your login/password from the phone, it is inaccessible. I just did traded in my iphone 11 this week with a smashed screen and got $600 for it.

Why do carriers offer deals for trade ins? Is there a risk of personal data theft if you do it?