My documentation is written for the Dynamic authentication interface for Android applications. In it, I mention what Android is, what has evolved and what features make it so diverse. I talk about the development program, Android Studio while giving you an insight into its useful features. I discuss the technical requirements of the code; what kind of development solutions are needed for the project. Since for me the thesis is a continuation of the independent laboratory subject, I present in a retrospective, how far I got in that, and show what goals I have set for completing it. In detail I present the lines of the thesis with what decisions were made contrast to them. In the documentation I also discuss the kind of changes the project has gone under during the semester, and the mistakes due to which I had to change it. Since the library can become public in the form of a module, I explain how to create a module and publish it on the Internet. At the end of the documentation I present an implementation with the module created, and then illustrate its operation and testing with images. Finally, as my closing words I tell you what experiences I gained during development, what were my difficulties, and what the future of the code could be.