This fast paced session explores building 2D and 3D mapping apps using a Mobile First approach with the ArcGIS API for JavaScript. Learn about important design and implementation considerations for building successful mobile JavaScript apps. Even though modern smartphones and tablets are powerful, they still aren’t as powerful as a laptop. By applying Mobile First development patterns you’ll learn how to build highly adaptable and responsive mapping applications that perform seamlessly and fast on a variety of device types and screen sizes.