Some resources for paddlers are available as a PWA.

PWA stands for Progressive Web App. It is a Website that is not only Mobile-friendly, but it can also do things that normally only  a native App can, eg. it can be used in Offline mode.
If added/installed to a homescreen of a mobile device, it woks like a normal App.
The benefit for the user of a PWA is that he can use it on moblile and desktop, depending on what is more convenient for a given situation.
For developers, it can mean less work. Eg. no need to write and test App's for iOS and Android separately, not depend on Apple's grace to get into the App Store etc.
Some things, only a native App can do (eg. easy payment), or can do it better (eg. speed). So a PWA is not perfect for all use cases, and some Projects choose to do both a Website and a PWA.

From our Resources list:
Progressive Web Apps for paddlers


Rivermap visualizes the navigability of river sections on an interactive map to give canoeists the best possible and quick overview of the current situation. The individual sections are color-coded depending on the water level and information recorded by paddlers provides valuable additional information. Using filters and linked data, the current situation and further developments can be analyzed more precisely.
All information is provided without guarantee!