dxcut is a library for reading, editing, and writing dex and odex files which contain the class definition and Dalvik bytecode used by the Android operating system. This project includes a disassembler/decompiler, dex optimizer, and hooking utils.
JEST will be the Java bytecode engineering Swiss-Army Jackhammer.
It will include a disassembler, class browser, obfuscator, optimizer, class editor, and bytecode debugger, and have an intuitive GUI.