AVDs

AVDs, or Android Virtual Devices, are virtual representations of physical Android devices used by the Android Emulator to run and test apps on a computer. An AVD combines a device type (the hardware profile), a system image (the Android OS version and runtime), and a set of hardware and software options to simulate a specific device configuration. Each AVD defines parameters such as screen size and resolution, RAM, internal storage, CPU/ABI, graphics acceleration, network settings, and sensor availability.

AVDs are created and managed via the AVD Manager in Android Studio. When creating an AVD, developers select a device definition, choose a system image corresponding to an API level, and customize options like memory, storage, and GPU emulation. The emulator can perform a cold boot or quick boot using a saved snapshot. AVDs can be edited, duplicated, or deleted.

Use of AVDs includes testing layouts and behavior across form factors (phones, tablets, TV, wear) and OS versions without physical devices. They support automated testing, debugging, and performance profiling. Limitations include that emulation may not perfectly match real devices and performance depends on host hardware; some hardware features (like certain sensors) may be emulated with caveats. GPU acceleration improves rendering, and hardware virtualization is typically required on the host. Alternatives to AVDs include physical devices and cloud device farms such as Firebase Test Lab.