If you have jailbroken your iOS device with the recently released Pangu jailbreak then you might be facing boot loop upon restarting your device. This issue is not very common but several users are reportedly having this problem. If you are one of them then don’t worry as there is an easy fix that you can try to get out of the loop. DagMeow at Reddit has pointed to a weird solution to this problem. Although he is experiencing this problem on his iPhone 4, it may not be limited to one device only. This happens every time you restart your device.
The solution to this problem is quite simple, and you can try this to fix the problem until the Pangu team releases a fix for it.
It appears that the actual problem is the Ambient Light Sensor of the iOS device. And the iPhone goes into boot loop only when you restart your iPhone while sitting in the dark room with low or no light. So as you might be guessing you can actually fix this problem by simply moving to a place with sufficient light or put your iPhone under a torch or desk lamp. That’s it now your iPhone will boot seamlessly without any loop.
Many users have confirmed this problem and have verified the working of this weird trick. However from the comments section at reddit it seems that this issue is limited to iPhone 4 devices jailbroken with latest Pangu jailbreak for iOS 7.1 and iOS 7.1.1. So if you’re facing the same issue let us know if this trick works for you.