@gogu1904: You'll have to reinvent the wheel, because KOReader's OTAManager is tied into the KOReader UI.
So, basically, hardcode a mirror, hardcode a path to the latest zsync file you care about, download it, parse it to get the filename of the latest tarball, download said tarball, unpack said tarball, then classic handoff to the startup script.
TL;DR: Feasible, but, err, why?

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