Dedexer is a disassembler tool for DEX files. DEX is a format introduced by the creators of the Android platform. The format and the associated opcode set is in distant relationship with the Java class file format and Java bytecodes. Dedexer is able to read the DEX format and turn into an "assembly-like format". This format was largely influenced by the Jasmin syntax but contains Dalvik opcodes. For this reason, Jasmin is not able to compile the generated files.
Read more about DEX disassembling in this blog entry or read this introductory presentation. Also see the pages maintained by Dan Bornstein, the original author of Dalvik about the Dalvik virtual machine that also has a Dalvik bytecode section.
Read more: Sourseforge