Some nice phone wallpapers / home screen images I adapted from posts on the /BMW sub-Reddit, which is full of this sort of thing, so you should check it out...
E30 M3 Grille ------- E30 Cabriolet Sunset
M3 Evolution E30 / E36 / E46 / E92 / F30
M5 Evolution Grilles ------- 3 Series Evolution Grilles