Changes Since 1.2
There has only been one change in the Theme API since 1.2.
New Info.plist Key
BTDisableArtworkSquaring key has been added to allow themes to adopt their own behavior for handling non-square artwork: by default, Bowtie will always return square artwork. For artwork with non-standard shapes, Bowtie will fit it into a square image, and then fill the background with a specified color (or black). If this key is provided and set to true, Bowtie will instead return the image in aspect-ratio resolution, and it will be up to the theme to display it properly.