My iphone camera wont even start!

Have you rebooted or done a hard reset since the update?

"Cold Boot (aka Hard Reset)
Unplug the power cord and shut the unit off. Press and hold the VOL DOWN and then POWER button at the same time for at least 10-12 seconds until after the start-up screen appears and is joined by some small print at the top of the screen then let them both go. If the TF booted the way it always does, you have not accomplished the task,try again until you have seen the 2 icons in the screen.

After a few seconds you should see a couple of shapes in the middle of the screen called "Wipe Data" and "Android". The right "Android" will have a green highlight fading in and out. Wait a few more seconds until the term "Cold Booting Linux" appears in the list near the top of the screens and let it reboot. If you own a keyboard dock be sure you do this with the dock connected.

Did you drop your phone? I'm adding a link that may help you. Follow the video instructions at your own risk. How to fix black and unresponsive iPhone screen

That exact thing happened to me, when you plug it in, does it show a battery with a very small amount of red fluid? If it does, leave it plughed in for about an hour or two. That's how I fixed mine, it was then fixed and Itunes recognizes it too. Hope I helped.

Try restoring it...here's how...

1. Disconnect the USB cable from the iPhone or iPod touch, but leave the other end of the cable connected to your computer's USB port.
2. Power off the device (Press and hold the Sleep/Wake button for a few seconds until the red slider appears, then slide the slider. Wait for the the iPhone or iPod touch to turn off.
3. Press and hold the Home button while reconnecting the USB cable to iPhone. When you reconnect the USB to iPhone, the device should then power on.
   
   Note: If you see the message "Charging... Please Wait" , let the device charge for at least 10 minutes to ensure the battery has some charge and then start with step 2 again.
4. Continue holding the Home button while iPhone starts up. While starting up, you will see the Apple logo.
5. When you see "Connect to iTunes" on the screen, you can release the Home button andiTuneswill display the recovery mode message:
   
   If you don't see the "Connect to iTunes" screen, then disconnect the USB cable from iPhone and repeat steps 3-6.

But you will lose all your data

omg this happend to me too!!! UPDATE ME IF YOU FIND AN ANSWER!

If the lens on the camera is stuck out, look to see if it's a little crooked. If it is, try to gently straighten it. If it still won't retract, try to gently push it in as you turn the power on.

Try using another cable or charger. A damaged charger or cable could cause it not to charge. 
Otherwise, contact apple or apple store for repair.

pls see this First !! B4 reset
Straight from Apple Iphone Manual
Camera is not functioning

1. Tap Camera, then point and shoot. Note: If you take a picture with iPhone turned sideways, it is automatically saved in landscape orientation. If you do not see Camera on the any of the multiple Home screens, check to make sure that Restrictions are not turned on by tapping Settings > General > Restrictions. If they are, set Allow Camera to ON or tap Disable Restrictions (in iPhone 2.1 software or later).
2. If that doesn't work, clean the camera lens with the cleaning cloth that came in the box with iPhone.

Met the same problem. I disassembled camera and found a lot of sand in lens transmission. I couldn't move lens even by hand. It was strongly jammed. I had to disassemble lens block completely to remove all sand. Now camera fully functional.

You have bricked it, to fix follow:
Hold the Power and Home button for 10 seconds Release the Power button, hold Home for 5 more seconds. Plug into iTunes