Apple Watch (Watchkit teaser 001)

Apple has left many questions unanswered regarding its upcoming smartwatch following its September unveiling. Representing a brand new form factor for iOS, the fashionable wrist-worn accessory sports a Retina panel which Apple bills as an “incredibly high pixel density” screen laminated to a machined and polished single crystal of sapphire (strengthened Ion-X glass on the Sport collection).

With today’s release of the official Apple Watch software development kit (SDK), watchful third-party developers have scanned the files in search of interesting tidbits and discovered references to pixel resolutions for both the 38mm and 42mm high Apple Watches, in addition to other previously unknown details worth mentioning.

The smaller 38-millimeter high Apple Watch will come outfitted with a 272-by-340 pixel resolution screen. The larger 42-millimeter device rocks a 312-by-390 pixel resolution Retina display.

I wanted to use the above values to calculate the exact pixel density of Apple Watches using the IsThisRetina web tool, but couldn’t because neither Apple nor the developer tools mention the exact Apple Watch screen sizes.

Apple Watch screen sizes (image 001)

Given Apple labeled the smartwatch’s screen as Retina-class, we can pretty much assume that an average human eye wouldn’t be able to discern the individual pixels when staring at the Apple Watch from normal viewing distances (that’s Apple’s unofficial definition of a Retina display).

San Francisco font

Other interesting findings:

  • The system-wide Apple Watch font called San Francisco (pictured above) supports Dynamic Type, an iOS technology that automatically adjusts the letter spacing and line height dynamically for maximum readability.
  • Developers can supply their own fonts, but won’t be able to take advantage of Dynamic Type should they do so and instead must optimize for readability themselves.
  • Watch apps are downloaded using the App Store on your iPhone, iPad, iPod touch or iTunes on your Mac or Windows PC. There’s no such thing as a dedicated App Store running directly on the Apple Watch.
  • Initially, third-party Apple Watch apps created using the Apple WatchKit are going to require a connected iPhone to function because much of the processing happens on the iPhone, not the Apple Watch. Actually, only storyboards and user interface resources are transferred to the Apple Watch.
  • Starting later next year, developers will be able to create fully native apps for Apple Watch – a feature no one saw coming before next summer.
  • Apple Watch icon sizes are as follows:
    • Notification center icon: 29-by-29 pixels (38mm Apple Watch) and 36-by-36 pixels (42mm Apple Watch).
    • Long look notification icon: 80-by-80 pixels (38mm Apple Watch) and 88-by-88 pixels (42mm Apple Watch).
    • Home screen/Short Look icon: 172-by-172 pixels (38mm Apple Watch) and 196-by-196 pixels (42mm Apple Watch).
  • Developers provide icons as full-bleed square images using the given dimensions and the system applies the circular mask automatically.
  • Maps embedded in third-party Apple Watch apps are static snapshots and not interactive within the app. Tapping the map takes the user to the Maps app.

Apple Watch (Watchkit Framework, slide 001)

  • Apple Watch does not support multi-finger gestures such as pinches although developers can add gesture recognizers to their apps. Out-of-the-box gestures supported across the system include:
    • Vertical swipes scroll the current screen.
    • Horizontal swipes display the previous/next page in a page-based UI.
    • Left edge swipes navigate back to the parent interface.
    • Taps indicate selection or interaction.
  • Notifications are provided in two forms:
    • Short Look: Provides a minimal amount of information to protect user privacy. A Short Look appears when a local or remote notification comes in and automatically disappears when you lower your wrist.
    • Long Look: Provides detailed information and more functionality after tapping a Short Look or when your wrist remains raised. Long Look notifications can optionally provide a dynamic interface and custom graphics and branding. The system automatically provides up to four action buttons in the Long Look interface (in addition to the always-present Dismiss button), based on the notification’s category. A Long Look notification does not disappear when one’s wrist is lowered  and must be actively dismissed by the user.
  • Subtle UI animations come in two forms:
    • Canned: Basically animations using a sequence of static images that can be presented quickly to the user at high frame rates.
    • Dynamic: Developers can also create animations programmatically, but Apple notes a dynamically animated interface adds a delay before playback can begin because the assets must be pre-rendered on an iPhone and transferred wirelessly to the Watch.

Just a quick though: because the first wave of Watch apps will do all the heavy lifting on an iPhone and stream results and UI back to the Apple Watch, using it may and will affect your iPhone’s battery life.

And those apps that use dynamic UI animations that get rendered on an iPhone may stop running if your iPhone isn’t present or the wireless connection has been disrupted. This won’t be much of a problem once Apple starts accepting native Watch apps later next year that run directly on the smartwatch hardware.

On the flip side, because all the processing happens on your iPhone you may not necessarily need to upgrade Apple Watch every year.

Apple Watch (Messages, Emoji)

In term of the guiding principles behind Apple Watch development, I deem the following excerpt from the official documentation the best summary of Apple’s approach to smartwatch user interfaces:

“A Watch app complements your iOS app, it does not replace it,” reads the document. “If you measure interactions with your iOS app in minutes, you can expect interactions with your Watch app to be measured in seconds. So interactions need to be brief and interfaces need to be simple.”

You can download the Apple Watch’s San Francisco font right here.

The official Apple Watch Human Interface Guidelines document is available through Apple’s website for developer resources here.

And if you’re really feeling like coding today, feel free to take a look at Apple’s official WatchKit Programming Guide.

More information is available at


  • Ryan Bartsch

    1st in line!

  • Okitavio

    Just a quick though(t)*

  • Donal Moore

    ”watch’ful third-party developers have scanned the files’, I hope this pun was intended lol

  • CS

    Although I haven’t tried one on yet, I will probably wait for the second generation. This one is bound to have issues (both hardware and software)
    And hopefully the next one will be even thinner/lighter. Not that it isn’t thin enough, but I think they can do better in the next update

    • Rowan09

      I read that the next gen will have the sensors they were initially bragging about.

  • Ian Leon

    WATCH seems kinda weak performance wise, it relies on the phone for every damn thing. the only thing the watch does is run a storyboard and delegate all the work to the phone.

    • Christian Mejía

      Like the pebble?

      • Ian Leon

        I don’t have a pebble, but .. I guess so yeah

      • Rowan09

        I have a Pebble and its a great watch. Smart watches are just for a quick glance in my opinion without having to look at your phone all the time. I use my Pebble when running to see my distance and times.

      • Gary LE

        Do u think the apple watch can use gps tracking for running WITHOUT the iphone?

      • Rowan09

        I don’t think so and neither does the Pebble.

  • n0ahcruz3

    I’ll wait for the 2nd generation.. Must last atleast 2 days if i buy an Apple watch.

  • sup

    Lol. My gear 2 neo has a resolution almost the same, cant see any pixels. Must be a “retina” display, too. It does 100 more things than the apple watch and battery lasts 3 days. Been out a year by the time apple watch is out. Nice try apple.

    • Tizen.

      • sup

        Thats the best part. Its actually a very well done watch os. Works great and super simple to use.

    • igorsky

      Also your Gear 2 Neo looks like shit, so enjoy.

      • sup

        Lol. Looks like a sleeker, thinner, better version of the apple watch without the moronic dial, and its half the price and does a hundred more things. I think I will enjoy it, thanks.

      • Rowan09

        Wasn’t the Gear 2 $300+ starting price? How can you compare it to an unreleased product?

      • sup

        Gear 2 NEO, thanks for reading my comments fully. Its $199. And the fact that yall are still waiting for the watch to be released was the whole point of my original comment. Nice to see you again, rowen! How was work? Oh yeah, u dont have a job, ur whole life is sitting in ur moms basement/attic reading this blog.

      • Rowan09

        The comment I responded to was only Gear not Neo. I’m not waiting on anything but you’re trying to compare an unreleased product to one on the market and that’s dumb. I wish I didn’t have to work and I have a union job building elevators in Manhattan, so don’t assume and I’m a married man with my own place. I’m also training to become a NYC Firefighter. Man I hope all of that hit you in the chest for making an ass out of yourself for assuming.

      • sup

        The neo is the same thing as the gear without the camera. And the fact that a “lesser” product, in your words, is still better than the still unreleased apple watch is very sad. The gear watches only work with galaxies, just like the apple watch only works with iphones, whats ur point?

        Not all comments are written for you rowen, so not all comments are all about you, apparently u think they are, saying “why should i care about this and that”. Let go of that ego, bro.

        Well im the president of the united states and im amazing . See, i can write stuff about myself too, doesnt make it true. Course if I really was obama, i would actually be an ass.

      • Rowan09

        You lost me. You tried to play me and I corrected you. You assumed I was some unemployed bum and you’re wayyyy off. How is the Neo better than the Apple Watch please let me know? How can you once again compare a released product with an unreleased one? Is this not a commenting system where anyone can comment? All I said was isn’t the Gear like $300+, I didn’t attack you at all. The Neo is a lesser Gear I didn’t make it that way Samsung did and that’s the reason it cost half the price. The Neo is a fitness band not a fully functioning smartwatch like the Gear. How does the Gear or Neo stand up to the Apple Watch I don’t know because it’s unreleased. This will be my last comment on this site since I’m making a name for myself. Later.

      • sup

        The neo is NOT a fitness band, it IS a fully functioning. It makes calls for gods sake, what are u talking about? U dont even know the product, so how can u comment at all. Im talking about the features of the gear 2 and gear 2 neo in comparison to the features of the apple watch that apple has provided. It does the same stuff and more, costs half as much, and has been out a while, no one is waiting around for apple to finally decide to release it. I thank samsung for making a “lesser” version of the gear 2, i dont need a camera on my watch, so i have the choice to save $100 and get the gear 2 neo which is the same but without the camera. At least i have a choice in the hardware unlike apple products. U get whatever apple allows u to have. And you have to wait for it.

        Btw, thanks for helping destroy the country with your union job. The rest of us appreciate it.

      • Rowan09

        Sorry I had to comment. My wife has a Motorola Bluetooth band that she can make calls from, read messages, etc and it cost $50. Destroying the country with a union job? What? If you work in construction without a union good luck on providing for your family. I hope you know all city jobs in NY are unionized, unions protect the employees instead of the rich owners. I love unions and anyone in NY not working for a union would prefer it because of the pension. What’s destroying America is greed and lack of moral values.

      • sup

        Its ok bro, ur just a pathetic liberal from the discusting new york city filled with the most rude people in the usa. Ur city smells like piss. Have fun dying from pissylung disease.

      • Rowan09

        Where are you from? NYC smells like piss? Looolllll these kids now-a-days. Do you work kid?

  • Mads Teland

    You can find it on this page on the offical Apple website: (.) com/watch/design/ (Remove spaces between dot and side of the dot)

    • Aaron

      To save everyone the trip; the 38/42mm sizing isn’t diagonal, it’s vertical height.

  • dothack

    next thing people are gonna be complaining how the iwatch runs there phone battery out quicker running all these background tasks and keeping bluetooth active alot.