For devices running Android version 5.0 (API level 21) or higher, each app runs in its own process and with its own instance of the Android Runtime (ART). ART is written to run multiple virtual machines on low-memory devices by executing Dalvik Executable format (DEX) files Build tools, such as d8, compile Java sources into DEX bytecode, which can run on the Android platform.

TLDR;

  • Compiles to dex file in a way to improve faster boot into apps
  • Responsible for crash reporting, watchpoints to debug, diagnose exceptions

features

  • Ahead of Time Compilation (AOT) & just-in-time (JIT) compilation
  • Optimized Garbage Collection (GC)
  • Better debugging support, including a dedicated sampling profiler, detailed diagnostic exceptions and crash reporting, and the ability to set watchpoints to monitor specific fields