An attempt to see if we can use a larger than standard def size, but smaller than full HD (retina) to strike a balance between memory use and quaity. Each image is presented at the SD width of 980px width.
69k: Half-retina, Better quality - 20% quality, 0.1 blur, 1470 x 810
211k: Apple's retina version - high quality jpg from their site, 1960 x 1080
55k: Retina, Worst quality 0% quality, 0.1 blur, 1960 x 1080
92k: Apple's SD version high quality jpg, 980 x 540