Here's a sneak peek:
From the Printable PDF of the Apple Watch Dimensions
Just print it out and see what they'll actually look like size-wise.
Another fun fact is that eight Apple Watch displays will fit into an iPhone 6 display. Not the Plus, just the regular iPhone 6. That really puts into perspective the challenges of making a device like Apple Watch usable.
Learning about how to divide the work between the iPhone app and the Watch was notable. Seeing how easy it is to bump up against a limitation or two like size and capability was also interesting.
I like to know how other people go about getting around hurdles like these, and Craig Hockenberry is good at showing his work. I highly suggest checking out the whole thing, but if you just want to skip straight to how you too can rock a “prototype” Apple Watch, the PDF is there for you too.