Hello! You can use both forms separately.
When you want to use a film roll, place the film roll and use the original camera cover.
When you want to use I'm Back, remove the film roll, fit the lid of the I'm Back camera, and then, as the video shows, it fits the camera on the I'm Back. Take the photo in digital mode, transfer the photos using the I'm Back WIFI to your cell phone and then transfer it to your PC, or if you prefer, remove the SD from the I'm Back and put it on your PC and transfer the Photos.
With the I'm Back is like this, you can make digital photos and when you want you can remove it and use your favorite film.