To all who question the feasibility of camera: you need to understand how camera works.
There are settings that allow almost everything save for very close objects to be in focus, so there's no need for an autofocus feature.
There are also settings that allow the picture to be captured quickly, there should be no motion blur. These are typically used in sport photos (It's not video so no stabilization is needed by the way, just dealing with motion blur).
Honestly the hardest part is the chemicals involved in making the instant film paper. Which should be a non-issue, considering how advanced they are in this field.