ZK - Java Web Framework Write one web application and provide an excellent user experience across desktops and touch devices such as the iPad, iPhone and android tablets without a separate component set ZK 8: Stay true to your Java roots and effortlessly keep up with front-end innovations. ZK is the best open source Java framework for building enterprise web and mobile apps. ZK Charts provides excellent interactive charting for your Java Web Applications! ZK Spreadsheet is an embeddable Ajax component for Java Web Applications. Exceptional data analysis and summerization with ZK Pivottable.