AppSync allows you to sync and install unsigned/cracked iOS applications.
I am not condoning piracy with the usage of this package. I personally use it for development purposes.
This is the last version of AppSync for iOS 4.0+ that Hackulous released before they shut down. AppSync may or may not be updated in the future.
This package contains an unmodified copy of AppSync for iOS 4.0+, and it functions the same just as the original from Hackulous did. It will still work for anything else that requires AppSync as a dependency, or to test your own apps in XCode.
Now, before you all bash me for supporting piracy, do keep in mind that there are legitimate uses for AppSync, particularly to debug iOS apps via Xcode if you don't have an Apple iOS Developer License. However, I can't stop you from using this for piracy, either.
I guess you can have peace of mind that this AppSync is a completely unmodified copy of AppSync for iOS 4.0+, unlike other pirate repos that rehost packages for no real reason (and apparently, sometimes do it wrong).