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This question could probably best be answered in two ways:

  1. What MobileSubstrate means to the end user, what they should know about it, and what "Safe Mode" is.
  2. A more technical explanation of how it works, why it works, the extent of it's abilities and things to look out for when writing code that uses it.

MobileSubstrate really gives jailbreaking it's magic, but unfortunately a lot of people have a great misunderstanding about this awesome piece of tech. Hopefully this question will clear the confusion.

asked 05 Feb '11, 00:32

aaronash's gravatar image


These points require a user answer and a developer answer. For #2 you can refer to the iPhone Dev Wiki article on Mobile Substrate


answered 05 Feb '11, 00:48

Optimo's gravatar image



To an end user, MobileSubstrate can be thought of as a safety net. It provides a framework for other software to work through that (generally) prevents the other software from actually crashing your device. MobileSubstrate instead realizes that the software has done something wrong, and drops to safe mode (disabling all software that uses MobileSubstrate), giving the user the chance to uninstall the offending software or log a crash report.

I'll leave the technical description to someone who actually works with it directly!


answered 05 Feb '11, 00:49

Endareth's gravatar image


edited 05 Feb '11, 03:14

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Asked: 05 Feb '11, 00:32

Seen: 10,156 times

Last updated: 05 Feb '11, 03:14

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