This thesis aims to extend the functionality of the current Frappe Gantt library in order to improve its user-friendliness. The library allows users to display and modify Gantt charts. The first chapter briefly describes the Gantt chart itself and where it can be used. The following chapters compare alternatives and analyze the current version of the Frappe Gantt library. Furthermore, changes are proposed based on their differences. Rest of the thesis describes the implementation of those changes. The thesis also includes user feedback on the implemented changes.