Photos on the iPhone has no option to sort the photo by size.
But you could start from the media kind albums. Look at the albums for RAW photos, Panoramic Photos, Portrait Photos, Live Photos and Videos, externally edited photos. These tend to be larger than the plain photos.
- Panoramic photos will have a larger width than regular photos.
- The file size of videos will depend on the duration, the format, and sampling rate.
- Portrait Mode photos are larger because of the additional depth map.
- Live Photos are larger because of the additional video clip with the animation.
- Externally edited photos can be huge, because the external editors may save the edited versions as a gigantic TIFF file and can increase the file size considerably. Some of my small JPEGs with just 3MB have been turned by the external editor into whopping 80MB files.
So you may want to start by weeding out the predefined albums for the different media kinds.
