The appxmanifest has entries for developers to fill in four different tile resolution images for each kind of tile (small, medium, wide, large), the different resolutions are: scale-180, scale-140, scale-100, scale-80.
From what I can tell if the developer fills in the largest resolution image (scale-180) the system will automatically scale it down when needed on lower resolution displays, thus it works everywhere. So do most developers really even need to bother filling in all the different tile resolution images? Seems like it will just bloat the size of the application for nothing.
My question about filling in the different resolution images not about whether I need to have the small, medium, wide and large images.