Introducing Ruler: Our Tool for Measuring Android App Size

This post introduces Ruler, an open-sourced Gradle plugin designed to measure and analyze the size of Android apps. Ruler works by replicating the App Bundle to APK generation process using Bundletool, then analyzing the APK with apkanalyzer to capture download and install sizes for individual files. It determines file origins by scanning Gradle modules and dependencies, and can also parse DEX files to approximate individual class sizes. Ruler supports ownership data to attribute app size contributions to specific teams and has been used at Spotify to reduce app size by over 9%.