Application Security
Copy protection measures:
-  Floating network licenses
 -  Hardware dongles
 -  Node locking
 
Tamperproofing:
-  Add antidebugging measures
 -  Checksum the code
 -  Plant decoys
 -  Avoid direct responses
 -  Code obfuscation
 -  Code and data encryption
 
Keep in mind that the attacker has complete control of your application.