"The flaw with this approach is that it's time consuming. After every 10 failed attempts, the chips need to be removed the phone, reflashed, and reinserted back

"The flaw with this approach is that it's time consuming. After every 10 failed attempts, the chips need to be removed the phone, reflashed, and reinserted back into the phone. Then the phone needs to be rebooted." What about the increasing enforced delay between individual attempts? I don't see people talking about that much. Is it easy to circumvent? The delay between the last few retries is an hour, for example. To make 10 attempts at the passcode takes 2h21m in total [1]. So to brute-force a four-digit PIN would take 10,000/2=5,000 attempts for the average case or 500 rounds (at 10 attempts each) at 2h21m per round for a total of ~49 days. Then you still need to add the chip replacement procedure. [1] http://cinnamonthoughts.org/2010/09/13/ios-passcode-waiting-intervals-for-failed-attempts http://cinnamonthoughts.org/2010/09/13/ios-passcode-waiting-... Edit: incorrect numbers and words.