Cytoscape is a standard desktop application for biological network analysis and visualization, but emerging problems include large network datasets that exceed desktop capabilities, demand for collaborative data sharing, and the need for self-publishing networks without web programming skills. CyNetShare is a first step towards a Cytoscape cyberinfrastructure that allows visualization of public network data files through an interactive web application using Cytoscape.js, sharing of visualizations via URL, and runs on both desktops and tablets.