Som' is wrong here! Help me clear this up. Apple and Android came out with their new toys they call smart watch
and I can't stop humbling why they gave us these wierd aspect-ratios? As usual, check out at guidelines. They've uploaded everything you need to get a closer look. I had to go thru this, since I designed the official Valentino and Feltrinelli App on these "weirdos" displays. See projects at Valentino Store and Feltrinelli Store
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Apple watch
Android Wear
Let's jump right in. As simple high-school math taught us, not everything looks the same to me. To be ironic, I call this the math.round() effects. As you can easily notice from the images below, PPi ain't the official metrics:
Apple Watch
model 42 mm: 1.53" - 390*312px
model 32 mm: 1.33" - 340*272px
Android Wear (hdpi)
model square: 1.65" - 280px
model round: 1.65" - 320px
Not to mention the war between these two gigantic industries to achieve the best screen quality in order to reach people's desires! Remember the contest between iPhone 6 plus and Nexus 5? Have you noticed they have about the same PPi?
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Finally, what screen resolution are designers supposed to create? Answers can be found between you as designer and developer next to you. Also do what I do, launch your virtual device and take a look at the configuration panel (e.g. using Android Studio).
Then give a try: create a view and test components between ui-assets and emulator. Afterall, they just put it out there. Now it's up to people like us to give the best shape design by testing new ui-patterns.
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Speaking of patterns take a look at what others have already came up with apple watch
Check out android wear concepts as well