Introducing UV Forecast for Apple Watch

Earlier this year, I launched a new Apple Watch app called UV Forecast. It’s a simple way to keep track of the sun’s strength at your location right from your wrist.

Hour-by-hour forecast
8-day forecast
Watch face complications

The first tab is called Today: it shows the current UV index, today’s forecasted high, and an hour-by-hour timeline of sun strength. It even shows sunset and sunrise between days.

The Forecast tab gives the forecasted high for each day one week out, and gives the time of day that the sun is the strongest.

No watchOS app would be complete without great watch face complications. UV Forecast includes complications for every watch face[1], and they look really nice. The app has a single option that lets you configure what complications show: either the high UV index for the day, or the forecast for the next hour.


UV Forecast wasn’t the first time I had used SwiftUI, but it is the first app I’ve released using it. Overall, I have fun using SwiftUI. It makes typically complex things like building lists so much more straightforward than UIKit, but there are still areas that seem like significant oversights.

Early impressions of Xcode 12 make it clear that SwiftUI is still young, and this year’s updates continue to make SwiftUI more powerful and bring it closer to parity with UIKit. I’m really excited to see SwiftUI grow and continue to lower the barrier to building truly great experiences in more places.

Dark Sky and Apple

When I started working on UV Forecast, I knew I’d be using Dark Sky as my source of data. I’ve been a Dark Sky user for years, and their weather API is top-notch.

What I didn’t know is that the very day I released UV Forecast, Apple would buy Dark Sky. They’ve now shut down their Android clients, but the API continues to be available.

I’m not sure whether Apple will discontinue the API at some point, but it seems sort of un-Apple-y not to[2]. If/when that happens, I’ll have to see whether there are any suitable replacements.

I have plans to make a few small improvements to UV Forecast, but the app is essentially in its final form with its current design and features.

You can get UV Forecast for Apple Watch for free on the App Store.

  1. And this fall with watchOS 7, you can use multiple complications from the same app at once.
  2. Or, even better, make weather data available in a system framework, like Maps.