I have lost all my contacts after updating my iPhone 5 to the latest iOS 7 system. I can barely inform anybody else about it and get their numbers back. How can I get my lost phone numbers back as soon as possible? Is there any useful way to help me? It is really annoying me for a long time. I will be really grateful for your help.

The iPhone Data Recovery is a very practical device which can restore iPhone contacts smoothly. It enables you to recover contacts from iPhone via the backup files on iTunes, no matter you areusing iPhone 5, iPhone 4S, iPhone4, or iPhone 3GS, or you just lost it. Besides, you can also extract your contacts from the iTunes backup when you lost your iPhone. iTunes can automatically back up your iPhone contacts and update it every time when you sync it. These are the three main methods to get your lost contacts back.

Tutorial 1: Extract iTunes backup to recover iPhone contacts

Step 1.Scan the backup file
Step 2.Recover your iPhone contacts

Tutorial 2: How to Restore Contacts from iPhone 5s/5c/5/4S/4/3GS

Step 1.Connect your iPhone to the computer
Step 2.Enter the device's scanning mode and scan it
Step 3.Preview and recover iPhone contacts

Tutorial 3: Recover Contacts from iCloud Backup Files

Step 1.Install the program and sign your iCloud account
Step 2.Download and export your iCloud backup
Step 3.Preview and restore iPhone from iCloud

Learn more: How to Recover Deleted Contacts from iPhone

Related Articles:

How to Find and View iTunes Backup Files
How to View iPhone Messages on Mac or PC
How to Save Contacts from iPhone to Computer
How to Get iPhone Contacts from iTunes Without iPhone
How to Export SMS from iPhone

It is easy to get your contacts back, provided that you have the contacts backed up before.

(a), Restoring contacts from iTunes backup. Simply run iTunes and connect your iPhone to the computer, then navigate to File > Devices > Restore from Backup.
(b), Recover from iCloud backup. Log in your iCloud account and then go to Setting > General > Reset > Erase All Contents and Settings, and then click "Restore from iCloudBackup".
(c), Another simple as well as free way is retrieve and extract data from iTunes backup by 3-rd party tool. Some iTunes Backup Extractor works well. As I know, It seems only iTunes Extractor is free. You can search in google and have a try. It can freely extract contacts without connecting iPhone to the computer.
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2), As you didn't have your iPhone data backed up. If you synced contacts with Facebook or Twitter before, it has great possibility to recover deleted contacts.

If by any chance you failed in above ways, I guess you have to buy the paid tools/software to get the contacts back. Or you can try Pro. version of iTunes backup extractor.

Read detail: how to restore lost contacts from iPhone 6s