The introduction of the thesis describes the purpose and usefulness of the developed application. This is followed by a presentation of baling grass or straw and the problems we encountered when we were performing the service of baling hay and a proposal for a application, which would solve these problems. Next is a general description of the smart phone and mobile operating system Android, which recently popularity is growing. Then followed by a presentation of the development environment Eclipse IDE and the Android SDK. Then some words are intended for the Java programming language used to develop Android applications and SQLite for working whit the database. The main part of the thesis is intended for the explanation of the application Baling grass, where first of all is a presentation of the data model, entities and extractors. Following chapters focus on the business logic and a description of Android components that run in the background. Next in line is a description of the user interface and the AndroidMainfest xml file. A few words are intended for the testing of this application and also a brief presentation of some ideas that would be included in the development of the next version of the application.