Gfrör.li app
Gfrör.li is Internet tool that is open source under the GPL-3.0-only license.The Gfrör.li app shows you the water temperatures of Swiss bodies of water. So ideal for Gfroerlis who still want to swim in the lake or river! So far, sensors are in operation in Lake Zurich and Lake Lucerne. Other sensors will follow.
The data come from self-developed measuring stations and are all updated several times an hour. More information about the project can be found at gfrör.li.