Iphone camera shows (and takes) negative images when I open it. So, instead of seeing a picture as it should be, all the colours are in negative.

Just connect your iPhone to your computer via the lightning or 30pin cable(depending on iphone model) and the phone will show up as a camera in your "MyComputer" folder. You can open up the images or copy them from there to wherever you want on your PC!

The image sensor is defective. There is no quick fix other than replacing the image sensor.

Have a look at the following link. You can see a collection of images showing the efect of damaged CCD sensors.
May be you can identify your problem:

http://www.piezas.biz/epages/wwwpiezasbiz.sf/?ObjectPath=/Shops/demo132390/Categories/CCD

If so, you will need to replace the CCD sensor. You can see this part and a video that shows how to dismantle it in the following link:

http://www.desmontalo.com/?p=317

Regads

Not sure I see a question as printed but I will assume you'd like some info on NEF versus JPG files. Simply put, if you're shooting simple pictures and just want to download, email, etc. then JPG will be fine. NEF produces an electronic equivalent negative meant to simulate a film negative. This gives you latitude to touch up the negative before printing and provides the most adjustment range and options. Many programs cannot use the NEF format so it will mean deciding how you want to save the pictures. Of course, they take up more file space as NEF - 10-12 MB instead of 6MB or so for big JPG files. I shoot all my pictures in NEF then convert them to JPG for normal use and printing. I burn the NEF to a CD or DVD for archive and future needs. All that takes up more space of course.

I experienced the same problem. I clicked on Settings, then clicked on General and clicked on Accessibility...then make sure that Off is selected for White on Black. Once I changed that setting...I could view my pictures in color and not in negative. Try it. What a relief ...cuz I thought something was wrong with my phone's camera.

Never had that camera, however, had the same problem -- the pink stripe and pink cast. Turns out the lens cover was slightly cracked and not opening and closing properly. Thus -- the pink cast.

Its problem of defective ccd imager in your Canon A95 camera and that part will be replaced.
Canon offers free of cost repair for ccd image problem in A95.
Click Canon CCD Imager Advisory for details.

My camera opens the "lenses" but it is black. Also up-date to the newest software 2.2 does not help. Before, it also showed that no space is anym more and some pictures should be deleted. I did not have any photos in the camera. The camera was new.

If you can use the LCD to take a photo and then use the LCD to review it later then the fault can't be with the camera. Have you tried checking the photos on another computer? Maybe your software is corrupt and needs uninstalling and then reinstalling again. Actually, from memory this camera has a few effects and one of them could be a negative. Check that you haven't switched the effect on by mistake. You'll find it in the camera's menu. What's causing the distortion I'm not sure.