Two handsets that have been well loved are the Samsung Galaxy S4 and the S3 and many owners still have them today despite newer models being out. If you own either of these devices you will be happy to hear about an unlock code that breaks the device free.
Owners of the Samsung Galaxy S4 and the S3 can now unlock their handsets with the leaked unlock code and it’s easy to do.
All you have to do is put in a new SIM card and then turn the handset back on again. You should then go to the dial pad and type in *#197328640#. You can then follow the steps outlined below.
 UMTS >  Debug Screen >  Phone Control >  Network Lock > Options  Perso SHA256 OFF.
Wait for around 30 seconds and you can then head to the main menu again and you should see Network Lock. Choose  NW Lock NV Data INITIALLIZ and you should now have a handset that is unlocked. This is a code that is said to work with other handsets, including the Samsung Galaxy Note 3 and 2 and others.