Since the release of the iOS 7 Jailbreak was a surprise to saurik, MobileSubstrate (which many tweaks run off of) has not yet been updated for the new operating system. Currently, after a reboot, MobileSubstrate will not reload leading several users to create their own unofficial patches.
Commenting on the MS Reload Fix saurik said:
(This is horribly dangerous: MSHookFunction is not designed to be used on functions that might actively be running; this makes Substrate get injected into launchd while launchd is loading launch daemons... no one should install this; it doesn't even solve the problem remotely correctly for anything but SpringBoard/backboardd, and will end up leaving you with Substrate having been randomly applied to different background processes.)
If you've jailbroken with evasi0n 1.0.1 there is a solution which may actually work; however, saurik recommends that you just wait a little longer for the official update.
In that light, it probably does work (it is not "dangerous" as I described the previous ones), but there is still little point in installing it because clearly a new build of Substrate would come out soon using this new feature I got from evad3rs ;P. (Which didn't happen yet as I took Christmas Eve/Day mostly as a holiday.)
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