Apple Watch sales are finally surging, which makes creating apps to support it well worth the challenge and effort.

The good news for iOS wonks looking to add wearable technology to their repertoire is that the same tools used for iPhone and iPad development, XCode and Swift, can also be used for the Apple Watch.

The big challenge comes from working with the device’s resource and form factor constraints, which means there are some initial considerations to think about before getting started.

For starters, and this holds for both design or development, the processing speed should always be a top consideration. For a responsive and pleasurable user experience, the key is to minimize the amount of work the Watch does on its own, while offloading as much of the burden as possible to the beefier, more robust iOS devices it connects to.

As well, debugging apps on the Watch itself is made more difficult by the hardware limitations. Frustrating is that it can sometimes take several minutes to launch an app on the device. As of now, there isn’t really any way around these resource issues, but the amount of debugging required can be mitigated by maintaining good test coverage in XCTest.

Also take note that Apple Watch has crucial size and input constraints: the dimensions are (obviously) smaller, but layout for Apple Watch works a little differently than normal AutoLayout in iOS, which means there’s a slight learning curve when moving between the two.

As such, designers should look wherever possible to lay out the views so that they maximize information content without sacrificing clarity. That’s always going to be a challenge, but the form factor is also one of the reasons we like the Watch in the first place.

Moreover, its limited battery life requires that developers be cautious about only asking it to work or communicate when it needs to. This is solved by making the app handle most of its thinking off the iPhone, because it’s faster, and because otherwise the Watch’s battery will quickly be drained.

Exciting times, and hope this post got the wheels turning on creating the Next Great Apple Watch app! Ready to dive in? Great, here are some tips that will make for a smoother development experience:

  • Tip 1: Almost all interactions start with a notification so they’re central to a good app experience. Send too many, and oops, it will be uninstalled. Send too few and it’s going to be underutilized. The context of interacting with a smart watch differs significantly from phones or tablets: it’s rarely the focus of the user’s attention, except when it needs to tell them something. Make sure the app is communicating timely and relevant information to the user, because it’s so much harder to ignore something on a wrist than in a pocket.

  • Tip 2: Find a way to leverage the unique information that’s gathered by being so closely attached to the user. This might mean using available fitness data, such as walking, or by noticing a long period of inactivity and looping that back into the app itself. Or it could be location data, such as GPS coordinates and speed of travel. Done well, collecting this kind of information can help build a cooperative relationship between the user and the app.

  • Tip 3: Limited navigation metaphors and capabilities means designers and developers need to work well together. With the Apple Watch, right now there are two choices in navigation: a carousel and a list. Limitations like this mean the focus should be on the real purpose of the app, then stick closely to it. Start by figuring out the feature or function that is core to the app, and (very carefully) build out from there.

  • Tip 4: Those little icons and bits of text that act as a shortcut from the app to the watch face are called complications. Complications are, well, complicated… but they’re worth it. With a confusing but limited array of options at each size, type, and location, complications convey a microscopic amount of information about the status of the app. They also keep it front and center in the user’s mind, so pick something that conveys as much about the app’s status as possible, then try to keep it relevant with timely updates when anything changes.

  • Tip 5: Typing anything at all, username and password, for example, is awkward, difficult, and inconvenient on the Apple Watch. Eliminate, if possible, the need for logins whatsoever. If that’s not possible, use alternatives like text message verification, or magic links. At the very least, integrate with apps on other devices to allow users access to a keyboard, and help them keep a bit of their sanity.

Conclusion

After a rocky start, the Apple Watch is ready to be treated like a first-class member of the Apple device ecosystem. However, while its small size and connectivity with other iOS devices is a strength, it also places critical limitations that designers and developers should bear in mind when making apps for it.

Overall, designers should approach the Watch with an open, research-oriented mindset, making sure to build prototypes and test the experience early on, because many of the familiar iOS paradigms will have to be reconsidered.

For their part, developers should carefully examine Apple’s documentation and code samples before diving in; and consider also adding unit- and UI testing to processes to minimize slowdowns caused by debugging overhead.