What is the worst thing you can encounter when using your Android smartphone? I think many people may say that it should be the loss of your important contacts. Many causes would result in the contacts loss, for example, deleting the contacts by a little mis-operation, or just an unexpected crash of the operating system of your smartphone. Fortunately if you have a limited number of the contacts, you can save them on your SIM card and even though the smartphone suffered the crash of the operating system, all the contacts can still remain safe. However, the space of the SIM card is quite limited that it cannot save all the contacts under normal circumstances and the data loss still happens every now and then. So it is necessary for you to know how to protect your contacts, and more importantly, how to retrieve important contacts on Android phone after you've lost them for a variety of reasons.