It won't hurt the cell phone simply because the lens is too small to et in that much light. With a regular digital camera, the lens is mant times bigger allowing much more light to reach the sensor - that is why they can be damaged.
But whichever camer, the sun will be too small to appear in the image with the detail of the eclipse. If you'veever noticed, the sun and moon appear much smaller in a photograph than they seem to the naked eye. That size difference means you would have to use a very long telephoto lens on the phone or camera in order for it to be big enough for the camera to show the details (i.e., The big black dot in the middle of the very bright ring).
