[eschwartz]

@MarjaE,

In addition to the somewhat... unethical... behavior of the Duokan developers, it is also worth noting that they do not publish their source code, nor do they actively develop their product anymore.
Not only that, but their software does not play nice with our community jailbreak, and has been known to cause mysterious problems with our software and/or their own uninstaller. It is a headache, really.

It is the combination of those four factors that makes us both unable and unwilling to support it.

...

It is possible someone who actually knows the answer to your questions (through lots of hands-on experience trying to use it, I guess?) can help you, but you are far more likely to get prompt and useful help for KOReader and its predecessors/forks/addons, which are both open-source and actively developed in part by the members here.