We have developed a new application Weather of the Czech Meteorological Office

The main task was to unify two existing applications and at the same time create a modern user experience that would meet the standards of current mobile development. The result is an app available for both iOS and Android that leverages modern technology solutions on both platforms. For the shared data core, we chose Kotlin Multiplatform (KMM), which enabled efficient database and network layer management across both operating systems. At the specific technology level, we opted for Jetpack Compose and Coroutines on Android, while we implemented SwiftUI on iOS. The result is an app that is not only clear and fast, but also technologically optimized and powerful. The design includes widgets that allow users to display selected weather information directly on the desktop of the mobile device.

The new app provides users with a comprehensive view of meteorological data. In addition to iconic radar images that allow you to follow the evolution of precipitation, the app includes animations of weather forecasts based on the ALADIN model. Users can thus continuously monitor, for example, changes in temperature, precipitation, cloud cover or wind over the entire Czech Republic. Alerts are also an important aspect - the application not only displays current alerts from the Czech National Weather Service, but also allows their management, including personalized notifications,  in the form of so-called push notifications. Adding data from measuring stations in turn allows you to monitor current values from specific areas, whether it's air conditions, water flows or the ventilation index. The app even includes unique information on tick activity, which is especially useful for people who spend a lot of time outdoors.

The actual development of the app was challenging and involved almost all the key teams, both on the Railsformers side and on the CHMI side. It included experts from mobile development to backend architecture, frontend solutions to specialists in meteorology, hydrology or air quality. One of the biggest technology nuts was adapting the proposed design for both iOS and Android platforms. You also need to account for a robust server-side infrastructure capable of processing huge amounts of data with minimal delays, which is an absolute must for an application of this scale and usage. During development, we also focused on optimization, which will continue to be crucial as the number of users grows.

The CZMU Weather app ranks among the top on the Czech market due to its clarity, accuracy and the personalisation options it brings to users. For example, it also allows you to set up an individual screen layout using portable banners that contain important meteorological information such as temperature, forecasts or bio-forecasts. Thanks to the intuitive "drag & drop" control, users can customize the screen according to their preferences. This is complemented by detailed meteograms, graphical displays of values and customizable notifications that highlight specific situations relevant to the user and location.

The "CZM Weather" app went into production in December 2024 and already boasts nearly100,000 registered devices. Initial feedback from users has been universally positive, praising both its appearance and functionality. In turn, this project has helped us to realise that even complex, technologically demanding tasks can be carried out reliably and efficiently. Within the application itself, further extensions and new features are planned, which we will of course inform you about again and bring you other interesting facts from the implementation itself.

If you're interested in what else we can bring to the table in the area of modern app development, keep an eye on our blog or contact us with your project. Innovation, flexibility and reliability - these are the values that drive us forward.