Pocket Disassembler is a disassembler app for Android; pick the architecture and key in the hex and it will disassemble it.
It is built as a front on libopcode from GNU Binutils.
I (David Gilbert) own the copyright to the front end. The source tree includes the binutils source; see the docs in there for the ownership of that code.
My frontend is licensed under GPLv3 (a copy of which is in the source), and Binutils is licensed under various version of the GPL; see it's source for details.
You can download an apk Here (there is also a SHA256sum file and a signed version of that which you should check).
The source is available from It's own github repository
The hex entry takes space separated hex entries; if you enter a series of bytes - say 01 02 03 04 - they'll end up in memory with 01 at the 1st byte, 02 at the 2nd etc (irrespective of any endian settings); this works nicely for entering x86 hex. If you enter more than byte quantities - e.g. 0102 0304 then the behaviour depends on the endianness. The first group always goes into memory at the lowest address, so 0102 goes before 0304 irrespective of endianness. For little endian the layout would be 02 in 1st byte, 01 in 2nd, 04 in 3rd, 03 in 4th for big endian it would be 01 in 1st byte, 02 in 2nd, 03 in 3rd, 04 in 4th byte. So for little endian 32bit instructions just enter the instruction as a whole word like ef000001 - this works well for architectures like ARM.