Perhaps in an attempt to become a real competitor Facebook (Even mobile phones) Google a device placed on all sites with Android, application Google+. There would be no problem, but this app automatically syncs all your contacts Google+ and brings them to the directory (in Contacts). So it is that the night I woke up that some of my friends ... "have been duplicated." Contact appears twice in Contacts.
To prevent and / or solve this problem, the simplest method is to turn off calendar synchronization of contacts with Google+ app.
Stop syncing contacts with the address book Contacts Google+.
1. Open the Google+> Settings.
2. From the "Settings", go to the account name (in the Accounts Settings).
3. After their account settings "Contacts"
4. In "Contacts” Uncheck both options.
1. Keep contacts up to date - Basically this option brings contacts Google Plus in Android Contacts.
2. Improve suggestions.
After uncheck the two options, all the contacts from Google+ or disappear from Android Contacts. This helps prevent duplicate contacts and presence of contacts who have not noted any number.
amtelefon.com – Remove Google Plus Contacts from Android Contacts.