A free program for Android, by SYSTWEAK SOFTWARE.
Duplicate Contacts Fixer for Android is a very powerful app to help you keep your contact list clean and organized. It can merge duplicate contacts, sort them by name or phone number, and even delete them.
If you have multiple accounts on your phone, it can help you keep them organized and remove duplicates in no time. The app also supports backup and restore.
How to use it?
It is very easy to use and will not take much time to complete the task. First, download the app from Google Play Store. You will need an Android device with a working internet connection.
The app is now ready to use.