'NoCameraFlash' Disables the Camera Flash on Your iPhone Outright
Yes, the iPhone's Camera application does have the option to disable the camera flash already, but for whatever reason, I always seem to goof up and mistakenly forget to turn the camera flash off every once in a while after using it, and then when I need to take a picture the next time and the camera flash goes off because I forgot to turn it off, it ends up screwing up the whole picture.
For situations like these, there's a new free jailbreak tweak called NoCameraFlash
by iOS developer Tom Brek, which will disable the camera flash outright no matter what you have the in-app setting set to. You can turn the camera flash to the "on" position, or even to "auto," and as long as you have this tweak installed, it will over-ride your setting and ensure that the camera flash doesn't go off.
The tweak also comes in handy for situations where you want to be discreet and want to be entirely sure that the flash won't go off without even having to take a second to glance at that camera flash indicator in your Camera application. It's kind of like an added layer of security for those discreet moments when you know you just can't let that flash go off.
The tweak works both from the Camera application itself, and from the camera that you open up from the Camera Grabber on the Lock Screen.
The tweak adds a preferences pane to the Settings application where you can enable or disable the tweak on demand:
If you want to download this tweak, it's available for free in Cydia's BigBoss repository.
iPhone with LED flash
iPhone 5 running iOS 7.0.4