I had jailbroken my ipod touch and then restored it so it is no longer jailbroken and I was wondering if there is a way to make my ipod look like it was never jailbroken so apple can not tell because I heard that even if your device is not currently jailbroken apple can still tell and will not fix it if anything goes wrong.
In theory they could technically tell that you jailbroke but in simple terms as user kba stated. If you preform a full restore while in DFU mode you should be just fine! I never had an issue getting replacement iPhones after erasing the phone entirely. Jailbreaking writes and manipulates files on the iPhone leaving it on the memory. Erasing the memory as you should know does not necessarily mean it erases and zero outs existing data. Thus creating the potential if apple really wanted to..to dig deep and find evidence of such data.
*also they could checkout jailbreak devs TSS center that houses iOS SHSH. Thus backing the case this person had an intent to be jailbroken LOL