Secure way to unlock full version via In-App Purchase

Question

I\'m planning to use In-App Purchases to unlock some features in my app. What is the most secure way to do this?

Originally I planned to set a Bool in the NSUs

Answer 1

Security through Obfuscation is the simplest way to go here (e.g. don't name your var "isPro" and perhaps don't have it's value be a simple BOOL but instead have it be some "magic" integer. Not foolproof but another speed bump to cracking.

As an alternative to using NSUserDefaults you could save a file to the app filesystem and then check it's contents at app launch.

Not sure it is worth the time and trouble though.