In 2023, we started the development of the new COBISS+ generation. The existing COBISS+ has become technologically outdated over the years, and problems have arisen with mCOBISS upgrades. The development of the new generation is thus based on the “mobile first” starting point, which will allow the use of the same version of COBISS+ with the same functionalities on all devices. In the presentation, we will look at the development of the prototype, the challenges that the implementation brought, and the role of statistical data on the use of functionality in the existing COBISS+ in the preparation of functionality in the new generation of COBISS + (data driven development). It is this data that is important for the preparation of the application, where a good user experience, an intuitive interface and the functionalities that users use the most are in the foreground. At the end of the presentation, the use of some of the most commonly used procedures in the new COBISS+ generation will be demonstrated.