Avoid discarding all images and option to select specific image to be part of pdf
When clicking X on top left, app should not force to discard all images. It would be better rather that the app:
1. Group images taken in each session so that user can export a specific group of images later into a PDF
2. Provide another view of all images taken in chronologically descending order in case user want to select specific images taken across groups to be part of multi page document.