That happened to me a few hours ago. Had to press home button to reset the flash and the camera. What did Google said about this? Did they just offered a replacement?

 

I think the camera app is a bit dodgy. I've seen a lot of people saying that the camera won't take a picture if you take a few one after the other (mine has also done this).

Some nice ideas in there but it really needs a fix.

 

Getting a replacement would be hard for me as I bought the N4 on the US but I'm not living there. I would have to ship it back, wait for replacement and pay shipping to my country again. I rather wait for a software fix, which I believe is the real problem.

 

The only temp work around i found while having this issue out and about was to turn on hdr, this seemed to stop the flash, by no means an ideal solution but it did seem to work.

 

Ive had the same issue and is quite embarrassing when taking pics of friends. I noticed that if you move the camera on what your focusing on than press the screen to refocus the flash will go off and than will function normally.