SimLab CAD Viewer is a versatile mobile app that enables users to view and explore 3D computer-aided designs and architectural models conveniently on both iOS and Android devices. This application supports the SimLab Archive File (.ZIM), which can be exported from SimLab Composer or through the Android/iPad Exporter plug-in compatible with software such as SketchUp, Rhino, SolidWorks, Inventor, 3ds Max, Maya, and Modo. The .ZIM files encapsulate all essential information required for rendering models on mobile devices, including geometries, colors, materials, textures, camera settings, scene states, and animations. Currently available for free, SimLab CAD Viewer can be downloaded from both the App Store for iOS users and Google Play for Android users. When users open the app, they are greeted with a selection of pre-installed sample models that allow for a quick demonstration of the app's features and capabilities. This intuitive design ensures users can effortlessly start exploring their 3D models right away.