Butterflies Germany is an app for sharing observations about butterflies from all over Germany. For each species the app contains sample photos and a short description of the species determination from the portal www.insekten-sachsen.de as well as a link for more information about www.lepiforum.de. Observations are geo-referenced via the GPS module of the smartphone and can be documented with a photo. The find reports can be synchronized by the user with the portal butterflies of Germany (www.lepidoptera.de). There is a quality check by specialists and, if necessary, a correction of species identification. The find points are displayed on the map of Germany and the photos in the gallery of the type concerned. To ensure all the features of the app, permission to camera, memory and location is required.