This one is currently my favorite Cydia tweak and its called “CameraButtons”. Once installed, it lets you to take photos and shoot videos with your iPhone’s volume keys, something I’ve always missed in my iPhone 4. CamerButtons has no springboard icon, instead a menu with handful of options is added to the iPhone’s native settings. The tweak gives you complete touch-free control of your iOS camera app. You can easily configure the volume up button, volume down button, and shake action to your desired function from the settings menu.
Here are the options available for CameraButtons:
Switches to photo mode if not already in photo mode and takes a picture.
Switches to video mode if not already in video mode and begins recording.
Snaps a photo or starts video recording depending on which mode the camera is currently in.
Switches Flash between Off, Auto, and On modes for compatible devices.
Switches HDR mode On and Off for compatible devices.
Switches between the front and back cameras for compatible devices.
There is also a Lockscreen Launch function which lets you open the Camera app straight from your Lockscreen by holding down the Volume Up or Volume Down button. You can download CameraButtons from Cydia via BigBoss repo for $0.99 only.
Here is a short demo video of CameraButtons: