Everything snapfiddle can do to an image
Six tools is not many for an image editor. The point is that they all run on the same canvas.
Generate a background. Cut your subject out of their photo. Put the two together and repair the seam. That is four tools in one sitting, with no export, no re-upload and nothing installed. An editor built around a layer stack would make you leave and come back between each step.
Remove objects and people from photos
Brush roughly over the thing you want gone and it is filled back in with matching background. No tracing, no layer stack, no export step.
Remove the background from an image
Cut the subject out of a photo in one action. This tool runs on your own machine rather than a server, so the image never leaves your browser and it costs no credits.
Replace part of a photo by describing it
Mark a region, type what belongs there instead, and only that region is regenerated. The lighting and framing of the original photo carry through.
Repair patches, seams and artifacts in a photo
Fill leftover patches and rough seams with matching background. This is the clean-up tool that makes the results of the other tools usable.
Generate an image from a text description
Describe a picture and it lands on the canvas as a normal image, where every editing tool works on it immediately.
Increase the resolution of an image
Enlarge a small or soft image while reconstructing detail, instead of stretching the pixels you already have.