Make application useful for users. You don't need virality built into application: "There was no built-in sharing function in the software that would have made

Make application useful for users. You don't need virality built into application: "There was no built-in sharing function in the software that would have made it inherently viral. The app was simply useful and users shared it with their friends. " Keep your variable costs low. They ommited keeping all other costs low.