How can I put an icon in the top left label and make fullscreen? Apple allocates some space on top for the digital clock and back label. I would like to customize it, but I can't find anything in the SDK to enable this.
The top strip of the Watch screen is reserved for displaying the page title, or occasionally links such as "Cancel" by default for modal views, and the clock. It is not possible to hide this.
It is possible to set an empty title for a page. Some settings will alsoplace a background image behind this text (if you set the mode to 'Aspect Fill', at least in the current Xcode 6.2 beta 3). However, the portion of the image at the top of the screen is simply occluded by a black strip, so this does not achieve what you want.
Additionally, Apple have specifically recommended against displaying logos on the Apple Watch screen, with the rationale that the screen is too small to display for the user anything but actual content.
To set the Global tint: