Mobile secret codes for android to unlock the hidden menus in your smartphone. Secret Codes App gives you USSD codes and other codes for all the major brands of mobile phones. USSD codes, or "secret codes", are simply codes that are used to unlock your phone's hidden features. You can now unlock the hidden portals of your Android phones and can crack the hidden menus by using mobile secret codes tips and tricks. Isn’t it exciting to get a secret code book for all mobile devices in just one app?