wtf is virtualapp?

VirtualApp (commonly abbreviated VA) is a software framework for Android that creates a sandbox environment capable of running other apps inside it. Think of it as a lightweight app-within-an-app container: other Android apps can be installed and run inside VirtualApp without being installed on the actual device system. The README and documentation are primarily in Chinese. The main use cases described include running multiple accounts of the same app on one phone (for example, two separate WeChat or WhatsApp accounts), running apps in a fully isolated environment for mobile security purposes, and enabling plugin-based architectures where an app can load and run other apps without requiring the user to install them manually through the device's normal process. VA works by intercepting all system calls that apps inside it make and redirecting them through its own internal framework layer. This lets it convince the Android operating system that the apps inside are properly installed, even though they are not. It supports both 32-bit and 64-bit apps, covers Android versions from 5.0 through 17.0, and works on ARM processors in both 32-bit and 64-bit modes. It also provides hook mechanisms at both the Java and native code levels, which developers can use to monitor or modify app behavior without needing root access on the device. The public GitHub code has not been updated since December 2017. A commercial version is being actively maintained and requires a paid license to use for internal, commercial, or app-store purposes. The README notes that hundreds of companies have licensed the commercial version, and apps using it have been launched over 200 million times. Integration involves three API calls: start the VA engine, install the target app into the VA container, and launch it. The full README is longer than what was shown.