Mobile Secret Codes for all Mobile device Brand Like Samsung iPhone Windows Q Mobile Huawei Blackberry and China etc.
All Mobile device have secret codes for testing necessary function are working correctly or not?
you can also manual check about your phone qualify and all function working correctly.

Discover the secret world of your iPhone Android and other OS base mobile! In some devices secret codes are available for the user. When those codes are typed manually from the phone dial-er or you can copy this code with long press on code.

Manually Type this code and execute.(some of code may harm to your Phone and change the settings so read description about what the code )