At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for watchOS (part 1).
1. I'm really excited about the new design system on all platforms. Liquid Glass is super cool. What do developers need to keep in mind when building for watchOS 26?
To adopt the new design system, start with updating your app for watchOS 10 – If you have done so, your app will be mostly ready for watchOS 26. For more information, see Design and build apps for WatchOS 10.
You can then look into Liquid Glass specific APIs to fine tune your app. This topic is covered in Adopting Liquid Glass.
If you have SwiftUI views using any custom style, make sure they are still legible and fit with the new design system.
2. Something that really stood out to me were updates to the Smart Stack, with the system prioritizing Widgets when they're most relevant. Tell me more about these new opportunities for apps.
Workout apps that record workouts using HealthKit may be automatically suggested on the watch face and appear in the Smart Stack without adding a widget.
Relevant widgets are a great way to present information related to a date, location, point-of-interest type, sleep schedule, or fitness condition in the Smart Stack when it is relevant. Relevant widgets don't need to display a empty state view when they are not relevant. They are only shown in the Smart Stack when relevant.
The watchOS 26 Design ToolKit in the Apple Design Resources includes a set of templates that you can use to layout your widgets.
3. Is the Wrist Flick gesture available to developers in the same way as Double Tap is?
The system uses Wrist Flick to dismiss notifications and incoming calls, silence timers and alarms, or return to the watch face. There is no separate API for the Wrist Flick gesture.
Apps that are using XCUIAutomation to make sure their user interface behaves as intended can use the XCUIDeviceHandGesture.flick to automate tests that verify that their app responds appropriately to the Wrist Flick gesture. For apps using automated testing, the XCUIDeviceHandGesture.doubleTap can be also be used to automate testing of the app with the Double Tap gesture. See XCUIDevice.perform(handGesture:)
4. Can HRV measurements be triggered on demand via API in watchOS? Guidelines or processes for enabling energy-intensive biometric sampling on development devices for IRB-approved research?
You don’t have direct control on the sampling rate in watchOS. You can use HealthKit (HKQuantityTypeIdentifierHeartRateVariabilitySDNN, to be specific) to query the HRV data, once the system has sampled and persisted the data to HealthKit. If that doesn’t help, we suggest that you file a feedback report with your concrete use case for us to investigate.
Specific to IRB-approved research using Apple Watch or its companion iPhone, you might want to look at this FAQ and SensorKit to see if they can be of any help.
5. What is the best advice for someone who is new to making a watchOS app that’s been on iOS and iPadOS?
You can start with exploring the system experience features on watchOS, such as notifications, controls, and widgets, and getting familiar with the system spaces, like Smart Stack, watch face, and control center.
Knowing the watchOS app design principles and practices is important as well. Design and build apps for WatchOS 10 is a great resource for this topic.
SwiftUI is an amazing across-platform framework, and you will use it to create your watchOS app. If you're already using it, great!
Keep in mind some watch-only constraints. Comparing to iPhone or iPad, Apple Watch has a limited battery and smaller screen size, which significantly impacts how people use your app and how your app works.
6. Was there any extension this year to the 7 day limit on querying Apple Health data on the watch?
There is no change on the limit this year. You can get this official limit at runtime using earliestPermittedSampleDate.
There are some exceptions, and so don't be surprised if you see some data types are retained longer.
The companion iPhone holds the full set of the health data. If you need to access the health data that has been purged from the Apple Watch, consider doing it with your iOS app, and then passing the result to your watchOS app.