Müller, ChristineFretag,UlrikeFuchs-Kittowski, FrankHosenfeld, FriedhelmAbecker, AndreasKudraß, Thomas2019-11-222019-11-222016https://dl.gi.de/handle/20.500.12116/30229It is easy to develop an Android-App and even beginners in programming can create an Android-App fast. Therefore, the question arises, it is worth spending time on design and architecture of such lightweight programs. But the frequency with which new An-droid versions are released and the changing demands of the users makes it just as necessary for apps to be flexible and extendable. Inforst develops apps for forestry that run completely offline. They are just as complex as desktop applications which meet the same tasks of collection, storage and exchange of timber data. The price for apps is far below the price for comparable desktop applications though. This puts even higher pressure on developers to develop reusable software components and reduce the costs for testing and refactoring. To fulfill these demands the use of Design Pat-terns can be helpful as is shown in this article at the example of the app “WaldFliege”15used to collect timber data.deText/Conference Paper