Today we’re excited to launch a new little app: Skylight Forecast. Skylight is an iPhone app that predicts your evening light. With the help of dozens of atmospheric factors and some of our own intelligent prediction technology, Skylight makes a daily forecast of the golden hour, sunset and afterglow — to tell you whether you can expect a spectacular sunset, an average glow, or barely anything at all.
Designed to delight and to inform in equal parts, Skylight is peppered with dynamic colors and backgrounds depending on the quality of the sun event. Even the icons are adaptive to the circumstances, changing based on the prediction.
OK, let’s take a step back: Given our previous apps are cameras, it may come as a surprise we’ve gone from photography to meteorology. And we’re just as surprised! We’ll chat about its origins in a bit. First, let’s walk you through what it does, because it’s more than just an app that tells you the time of sunset and golden hour.

At first glance after opening the app, you’ll see a rainbow-like path of the sun across the sky. This beautiful abstraction represents tonight’s sunset — and it changes its colors and appearance depending on our forecast.
Below, three expandable cards tell us about the important events of the evening: Golden Hour, Sunset, and Afterglow — and our forecast of their quality.
Each of these items is a card containing details about the sky’s appearance and details about our forecast. Let’s talk a bit more about each one.
The Main Event(s)
Let’s start with Golden Hour. It’s a long known fact that golden hour is the best time of day for photographers to go out shooting. In that (approximate) hour before sunset, when the warm light combines with long, dramatic shadows makes every photo feel magical. Some days are more magical than others. It’s our hope this takes some of the guess work out of planning shoots.



Then we have the sunset. It’s technically defined as “Civil twilight” — a definition outlined by the sun reaching an angle of about 18 degrees below the horizon.

Our prediction of sunset’s appearance is based on several factors that we will go into more detail in a future blog post — but surprisingly, two really major influences are geographic latitude and the aerosols in the atmosphere. We had a huge journey in finding what makes a sunset ‘Spectacular’. Stay tuned for a deep dive into that!
Then we have Afterglow. Sunset enthusiasts will tell you to never go home right after the sun disappears below the horizon because the show has yet to start. Sometimes the most colorful and vibrant skies appear during this “Secondary Sunset.” This event typically 15 to 20 minutes after a brilliant sunset has dropped below the horizon. The illumination of nearby clouds is softer and the color is a blend of all the colors in the primary sunset.

And that’s the app (for now). But there’s more than the app. There’s our widgets:

You don’t even need to read the text to get an idea of what’s happening. The color and vibrance of the widgets will give you a glanceable summary — and the same goes for the icons, which change significantly depending on the forecast.
Of course we have support for Lock Screen widgets as well: it works great with the always-on iPhone 14 Pro screen.

Funny story, actually: widgets are where Skylight began.
The Story Behind Skylight
It started when Apple announced widgets were coming to the iPhone with iOS 14. Whenever Apple debuts a new technology, we brainstorm ways we can integrate it into our apps. As photographers, our minds went to light.

We make apps that touch the real world. We love that people go out and capture the magic of everything around them with our cameras. But what if we could bring people outside? We could do a golden hour clock, perhaps?
What truly motivates us is building apps that excite us, and we’ve never said, “I wish I had a better golden-hour clock.” We thought, “Would it be killer to have an app that tells us about the golden hour? It’d be so cool if an app could tell us that we should plan an evening trip!”
This lead us down a rabbit hole. We were curious why sunsets tend to be crisp and colorful in the desert and soft and pastel in the tropics and cloudy latitudes. We did a deep dive into meteorology, studied the impact of air quality on sky coloration when combined with different temperatures and latitudes; coloration of clouds from different altitudes; the impact of surface temperature; the relationship between water vapor and color absorption — and that was just the start. As it turns out, there’s a near-infinite set of contributing factors behind the phenomenon we’ve come to appreciate and call ‘sunset’.
Then we built a backend, and dove into the weather data from different API providers. After finding a weather provider that we felt had the best real-time data for US and beyond we fine-tuned our algorithm over two years and quickly realized this was more than a widget.
This could be its own app!

When brainstorming the name for our app, “Skylight” seemed like an obvious choice. The ambient light in an outdoor shooting environment is composed of two elements: the light from the sun, plus what the sky reflects back to earth. The sunlight that strikes the sky creates what we know as “skylight.” The more strongly skylight exerts its influence on our images the greater the presence of blue.
You may wonder how we managed to juggle work on Skylight while continuing to update and invest in our apps. Well, we didn’t do it alone. Skylight is a collaboration with Ryan McLeod, winner of 2017’s Apple Design Award for Blackbox! It was a dream to work with Ryan on this totally new project.
A final word on privacy and security: User privacy is and will always be a priority. Our famous stance is that a camera should be private — and as such, Halide gathers zero data.
Some companies might have been tempted to harvest the wealth of location data and such in Skylight, but we actually went through great trouble to know less about you. At the expense of an optimized cache we do not save any information about your location or locations you select on our servers. All predictions are generated in real time and saved locally on your device.
Like all our apps, you own your data.
A new dawn?
And that’s Skylight 1.0. We have ideas for where we’d like to take Skylight, but it’s tricky being a bootstrapped indie team. We’ve also put an unreadable amount of work into such a humble utility, and we’ve decided that this is the right point to get this in people’s hands and sees if others dig our results much as we do.

We’d love to get your feedback on where to take this next! While building tools for photographers will always be our focus, this app is also for the many inquisitive people who enjoy nature and are interested in knowing the spectrum of sunsets and evening skies.
Launch Sale
Skylight is a fun utility, and we’re pricing it as such. In its current form, it will cost $1.99 a month in our launch sale. However, if you sign up for the annual subscription, you can lock in a $9.99 a year rate, and we’re including a one week free trial.
While we believe very firmly in offering one-time-purchase options for our app, we just can’t do that for Skylight. Our weather data provider and servers have ongoing costs. However, we are still absolutely committed to offering one-time-purchase options for any current and future apps that don’t have ongoing cost.
This cool little experiment is our first announcement of the year, and we’re proud that it’s finally seeing the light of day. Let us know what you think — either by writing us directly (we read all our email!) or on Twitter, Instagram, or Mastodon. Your feedback will help us figure out what’s on the horizon!