Open-source, cross-platform Qt based IDE for reverse-engineering Android application packages. It features a friendly IDE-like layout including code editor with syntax highlighting support for Android's *.smali code files.
Please head over to Releases page for downloading.
Information on building from source is provided in the Wiki.
Same as apktool, APK Studio is neither intended for piracy nor other non-legal uses. It could be used for localizing, adding some features or support for custom platforms, analyzing applications & much more.