Explore the intricacies of JavaScript performance in mobile web and hybrid apps in this JSConf.Asia 2015 conference talk. Delve into the world of PhoneGap and Apache Cordova, examining how JavaScript developers can build cross-platform mobile apps with native-like performance. Discover the key factors that constitute "native performance" and learn about common pitfalls that lead to poor JS performance in hybrid apps. Gain insights from developers of popular control frameworks like Ionic and Famo.us, and explore tools and techniques for diagnosing and solving performance issues. Uncover design tricks to achieve an authentic native look-and-feel in your hybrid apps. From WebView tax and memory footprint to DOM thrashing and CSS gradients, examine various aspects affecting performance. Learn about the importance of garbage collection, event handling, and memory management in optimizing your mobile web and hybrid applications.