There is a new IOS model being introduced every year. Those who like being seen with the latest device simply sell the old one and add cash to buy a new model. Subscribers who are on a two-year plan are lucky since they can sell the old unit and get a new model free. Despite new models coming out every year, IOS devices are still quite usable even if they are a few generations behind. Hence, it is quite normal to see used IOS devices being sold in malls and online sites. However, some buyers find out late that the device they bought is unusable. Here are things to note before buying a used IOS device.