Mercury Weather app icon

Mercury Weather

Chart-based weather app with a side-by-side layout on the unfolded Duo

View on the App StoreFree + IAPBuilt for Duo

Mercury Weather is built for iPhone Duo (it uses the fold, Split View or the outer display) as of .

About this app

Mercury Weather, from the two-person team at Triple Glazed Studios, is a weather app built around clear charts rather than dense tables of numbers. It covers the everyday basics, including hourly and daily forecasts, a radar map, rain forecasts and weather notifications, and adds features that are less common in mainstream apps: a Trip Forecast for planning travel, hurricane and storm tracking, tide forecasts and climate normals that show how today compares with typical conditions. Home Screen and Lock Screen widgets and an Apple Watch app keep the forecast visible without opening the app. Version 3.8.1 is the release the developers describe as unfolding Mercury on iPhone Duo. On the unfolded display the app places your saved locations next to the forecast, while folding the phone returns it to the standard iPhone layout. The update also lets you open two Mercury windows side by side to compare two places, and adds an hourly history view that shows the previous 24 hours when you pull the hourly forecast back past the current time. Mercury is free to download, with monthly, yearly and lifetime subscriptions available as in-app purchases, including family options. It suits people who want a quick visual read of the forecast and who track the weather in more than one place.

Features

  • Chart-based hourly and daily forecasts
  • Hourly history covering the past 24 hours
  • Trip Forecast
  • Hurricane and storm tracking
  • Tide forecasts and weather normals
  • Radar map and weather notifications
  • Widgets and Apple Watch app

How it uses iPhone Duo

The developers' notes for version 3.8.1 say Mercury is ready for iPhone Duo: unfolded, it shows your locations next to the forecast, and folded, it returns to the familiar iPhone layout. The same notes say you can open two Mercury windows side by side to compare the weather in two places. DuoDiscover has not yet tested it on an iPhone Duo.

Compatibility

TierBuilt for Duo
Uses the foldYes
CategoryWeather
PriceFree + IAP
Verified · developer statement
Added

What the tiers mean: Understanding iPhone Duo app compatibility ›

Developer

Mercury Weather is developed by Triple Glazed Studios LLC.

Official website: mercuryweather.app

Get the app

Discuss Mercury Weather in r/iPhoneduoapp ›

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Mercury Weather on iPhone Duo: FAQ

Is Mercury Weather optimized for iPhone Duo?

Yes. Mercury Weather is Built for Duo (Made for iPhone Duo): it uses the fold, Split View or the outer display. Verified on October 9, 2026 (developer statement).

What does Mercury Weather look like on iPhone Duo unfolded and folded?

The developers' notes for version 3.8.1 say Mercury is ready for iPhone Duo: unfolded, it shows your locations next to the forecast, and folded, it returns to the familiar iPhone layout. The same notes say you can open two Mercury windows side by side to compare the weather in two places.

How much does Mercury Weather cost?

Mercury Weather costs Free + IAP on the App Store.

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