Systems, methods, and computer program products to perform an operation for validating and adapting a GUI structure to a screen of a client device. The operation comprises receiving by the client device a software agent together with a device dependent arrangement rule. The software agent is adapted for analyzing received GUI code for identifying GUI elements to be rendered on the screen and determining a relative arrangement of the rendered GUI elements. If the relative arrangement is not compliant with the device dependent arrangement rule, the software agent determines a distance between GUI elements of the relative arrangement and a relative arrangement of the GUI elements in accordance with the device dependent arrangement rule, amends the GUI code to re-arrange the GUI elements towards the improved arrangement, and re-renders the GUI elements for the screen using the amended GUI code.