How to recover lost contacts on iOS and prevent it from happening again

The trouble with being connected all of the time is that when something bad happens to the data stored on one device, like losing your contact list, it can quickly spread like wildfire across all of your devices. If you do end up losing your contacts, there are some steps you can take to hopefully get most if not all of your contacts restored.
The following will guide you through the recovery, restoration and prevention techniques to keep all of your contacts safe.
check contact settings

First steps, don’t panic

Place device in airplane mode – Like throwing an electronic device into a bag of rice when you spill something on it, turning on airplane mode when you think that you have accidentally deleted or erased your contacts from your iOS device is a good first step to take. This could allow you the opportunity to log on to your account from another device or browser and see if your contacts are still available online before your device has a chance to sync.
Check for a misconfigured setting – One common mistake that is easy enough to rectify is a setting that could have been modified to either stop syncing your contacts or to hide entire groups of contacts on your device. Check your mail settings to ensure that you have enabled contact syncing. Also, from within the Contacts app, tap on Groups and see if you may have hidden some of your contacts from view.
Isolate other devices – Ideally what you are looking for is a device that has been powered off when you first discovered that your contacts were missing. You don’t want that device to sync and possibly delete your contents as well. One tip would be to turn off your wireless network, unplug your Ethernet cable, or take the device to a location where it cannot connect to the internet and sync. This is where improvements in how OS X works can hurt you as your Mac can take a power nap and sync your accounts when you thought your Mac was otherwise asleep.
extract lost contacts

Where to look

Export contacts from the cloud – Your best bet is to try to log on to your account from a device or computer that you have not configured as a syncing destination for your accounts. Most if not all of the popular email providers support browser-based access to your contacts online. Each has a different way to export your contact list, but they all seem to be able to export to either a CSV or vCard file:

Extract contacts directly from a device – If you do have an iOS device that does still have your contact list intact, you can access the contact information on the device. If you try to use iTunes to sync your contacts off of your iOS device, you will be warned that the device will be wiped prior to syncing. Instead what you want to use is an app like Ecamm’s PhoneView ($29.95, Mac) or Macroplant’s iExplorer ($34.99, Mac/Windows). With either of these tools you can easily access your contact list and export it to your desktop.
Browse iTunes iOS backups – When you perform a backup using iTunes, the backup files are saved in a place where you can access them. Using tools like addPod’s JuicePhone (Free Mac), or Macroplant’s iExplorer (mentioned above), you can browse and extract files from your devices’ iTunes backups. Depending on how long it has been since your last iTunes backup, you may be able to restore the majority of your contacts.
rebuild contact list

Start the restoration process

Recently sent and received email – The good thing about your contact list is that it is was full of people and businesses you keep in regular contact with. Rebuilding your contact list from scratch can happen surprisingly fast. From within Mail, you can tap on the “From” and select add to contact or add to existing contact. Since you are reading the email that was sent by someone you know, you should be able to quickly re-create a good portion of your email contacts.
Outgoing and incoming call lists – Another good place to check for rebuilding your contact list is from your call history in your phone app. If you are not sure which phone number belongs which person, you can use an app like WhitePages (Free, Universal) to reverse lookup the phone number. For just $3.99 through an in-app purchase, you can buy a subscription that will allow you to reverse lookup unlimited phone numbers and addresses for 30 days.
Online phone records – If you no longer have access to your recent call list on your iPhone, you may be able to access your usage details by viewing your wireless bill online. Simply tapping on a highlighted phone number on iOS, or by highlighting the phone number on OS X in an editor like TextEdit, you can create a new contact or add to an existing one. Depending on the detail contained in your usage information, you may end up copying and pasting phone numbers into your WhitePages app (mentioned above).
Scan return address labels and business cards – Another good source of information is your regular mail. You can use an app like SmileOmMyMac’s PDFpen Scan+ with OCR ($4.99, Universal) to take a photo of the corner of your letters. It will turn the photo into text that you can copy and paste into your contacts. Likewise you can go through your stack of business cards with an app like SHAPE’s Business Card Reader Pro($6.99, iPhone). That can turn a photo of a business card into a contact record.
prevent future contact losses

Prevent future losses

Duplicate contacts across multiple accounts – Within iOS you can eliminate viewing duplicate contacts when your device is configured to sync to multiple services like Yahoo, Google and iCloud by linking contact records. To combine duplicate contact records you must first edit the contact, scroll all the way to the bottom of the record, and add the record that you want to associate with it. This way if you happen to have the same person listed as a contact on several different services, you will see only one record in your Contacts app.
Backup regularly to both iTunes and iCloud – It is easy to set and forget that you are backing up your iOS device to your iCloud account. But remembering to backup to your iOS device to iTunes on your computer may occur less often. While a restoration from iCloud may in fact restore your lost information, having the backed up information stored in a location you can access as you can with an iTunes backup can prove to be useful.
Export contacts lists and send them to yourself – When it comes to managing your contacts on iOS, an app like Yoni Tserruya’s Simpler Pro ($2.99 Universal) can make backing up your contact list a breeze.  With just one tap you can quickly export your backups to Dropbox, Google Drive or even Email yourself a copy.  On OS X, you can simply create a vCard backup file of your contact list directly from within the Contacts app.