In late June 2015, I published (more or less simultaneously) two ebooks with a virology theme. These are “A Short History of the Discovery of Viruses“, which sells for US4.99 on the Apple iBooks Store, and “Influenza Virus – Introduction to a Killer“, for US$9.99. Both were composed using Apple’s iBooks Author app, and published in iBooks format, for reading with the iBooks app on Mac, iPad or iPhone. Both have been updated since.
I am amenable to publishing PDF versions of both if there is any demand – however, this means losing some of the iBooks functionality.
Sadly, neither is available on the South African store, so if you would like one, go to the US/UK stores via iTunes, and buy!!