你买后没有设置这个功能吧? With Find My iPhone Activation Lock, your Apple ID and password will be required before anyone can: Turn off Find My iPhone on your device Erase your device Reactivate and use your device 卖的时候是不能有这个setup的,要不别人用不了。如果你没设,click Yes. 另外bestbuy有这个你可以看下: Guaranteed minimum of $200 toward the new iPad Air 2 with trade in of iPad 2nd generation or newer + 50 coupon toward a new iPad Air 2 = $250 http://www.bestbuy.com/site/promo/trade-in-offer-129347