Avoid apk cracked [closed]

Answer 1

I agree with @Tom van der Woerdt Implement your own licensing library

I'd also refer you to check out this from Google I/O 2011:

Evading Pirates and Stopping Vampires

http://www.youtube.com/watch?v=TnSNCXR9fbY

EDIT:

The Presentation Notes from Evading Pirates and Stopping Vampires

Some basic keypoints

• Modify the LVL
• Implement LVL Tamper Resistance
• Use obfuscation
• Add reflection