This is exactly as described above: two files are generated if you use the 16:9 format, without the user making any edits intentionally, it is the iphone which makes the edit (crop) from 4:3 to 16:9. Then E is added to the name of the "edited" file (even without the user knowing about any edits!)

The problem with all this is that most people consider the 16:9 (or whatever they chose) as the default which they for example want to transfer to computer etc. Now what happens is that two files are transferred of the same shot and for some you want to delete or keep the E file and for some the other one. Very confusing when transferring or arranging by name photo files.

The user friendly way of handling this would be that the original shots would be given the prefix "O" (=Original)  but of course only if there are two versions. This way all the choices one makes when taking the picture determines which photo is original to you and that should be saved without any stupid prefixes like in normal cameras and the native resolution shot could be saved in the phone files with "O" prefix.