On a scorching summer day, one sidewalk is bathed in building shadows while the other bakes in direct sun. You can feel the difference, but no map ever tells you which way to walk. I built Shade Compass to solve that problem.
I started this project because I noticed the gap myself. During brutal heat waves in Korea, navigating even a short walk becomes a strategic problem—especially if you’re pushing a stroller, walking a dog, or just trying to avoid heatstroke on your commute. Existing maps show terrain and traffic, but they ignore the one thing that actually matters in summer: where’s the shade right now?
The app was already available on Android, and I’m happy to bring it to iOS users today.
What it does
- Real-time shadow maps: Open the app and immediately see which buildings and street trees are casting shadows at this exact moment. Drag the time slider to preview how shadows shift at 3 PM or 5 PM.
- Left or right guidance: Instead of north-up navigation, the map rotates to your walking direction and tells you plainly whether shade is on your left or right. No ambiguity—just actionable information.
- Shaded route planning: Enter a start and destination, and the app calculates a walking route weighted for maximum shade coverage. You can compare it side-by-side with the fastest route and decide if an extra few minutes of walking is worth staying cooler.
- Walking mode: Follow your route with a screen that rotates with your direction and displays remaining distance. The screen stays on so you can hold it comfortably while navigating. No turn-by-turn voice—just visual guidance.
- Favorites and recent destinations: Star your frequent spots for one-tap access to shaded route options.
The shadow calculations combine national building data (9.6 million structures), street tree information (1 million trees), and solar position algorithms from NOAA to estimate realistic shade patterns across most urban areas in Korea. The background map uses official government data.
This app is for anyone who walks outside in summer heat. Commuters choosing which sidewalk to use. Parents with strollers where ground-level heat reflection is brutal. Dog owners searching for shaded alleys in early evening. Runners and walkers optimizing routes for comfort rather than speed. Anyone heading out on a hot day who wants to avoid direct sun.
Shade Compass is free, requires no sign-up, and runs entirely on public data. Banner ads support server costs. If you spend time walking in urban Korea during summer, download it on the App Store and let me know what you think.
App Store에서 다운로드: 그늘나침반 – 그늘길·그늘지도·산책 내비
Android(Play Store)에서도 다운로드: 그늘나침반 – 그늘길·그늘지도·산책 내비
Official page: reactiveworks.dev/apps/6799209656
Update history: ahngo13.github.io
Leave a Reply