With browser adoption of WebGL on the rise, developers can start to reap the benefits of GPU-assisted rendering and 3D graphics. The WebGL API has a notoriously steep learning curve, but there are a number of open-source projects to accelerate getting geospatial data visualized.I'll compare the pros and cons of developing geospatial applications using native WebGL verses general-use and geospatial-specific WebGL javascript libraries. Some libraries include three.js, lightgl, PhiloGL, CesiumJS, OpenWebGlobe, and OpenLayers 3. The use of WebGL also has benefits beyond 3D visualization. I'll also talk about how we can leverage better performance out of 2D or 2.5D maps by using a WebGL renderer through my experience developing a web-based urban data processing and visualization framework. I'll go over the types of 3D data visualization, from globes, to abstract 3D representations, to 3D modeling, and whether any of this works within mobile devices.The use of 3D maps will also be considered from a data-driven and user-centered design and cartography perspective--their inclusion should consider whether the user and data actually benefit from expressing geospatial dimensions. I'll address some common geospatial pitfalls, from 3D to 2D, and when maps can hurt more than help, through real-world examples.