I have compared two images taken on iOS 8.1.2 and iOS 8.3. The images taken on iOS 8.3 could not be placed into a word doc via python-docx because it was throwing exception 'Unexpected EOF' in the image/helpers.py file, when it was trying to parse the string value for that field. I traced through the code and then looked at the images in a hex editor.

Both images and their EXIF data seem to display correctly without error in a number of image programs.

I think it's possible that in the EXIF data, (which usually has a tag_code, value_count and value_offset directory for each EXIF field), the value placed in the 'value_offset' area is the value itself if it can fit within a 4-byte field, else a relative address is placed to where that value is actually stored. See image below for a (hopefully clear) explanation of what I found.

Thanks.
screen-shot-2015年06月04日-at-9 24 45-am