By Atari - APX Catalog Number 20236
Kangaroo is one of the few uncredited games published by APX. It is simply labeled with an Atari copyright. Jim Leiterman, who was a Research Engineer at Atari from 1982-1984, explained why:
General Computer was contracted to only do a 5200 version. While at Atari I had written a reverse disassembler that converted binary files back into source code with some documentation. I went through and corrected the mistakes of the tool to build the 800 version and sent it over to APX. They published it with no credit back to me as I requested. So essentially it was an internal hack!This software is not available for download. The software is copyrighted by Atari. We do not have permission from the copyright holder.
Eventually General Computer came out with a cartridge [for the 800] version but mine was better because I corrected for the colorburst. So mine had red strawberries and theirs had a purplish red or some non-red color.