I'm working on a full-screen fixed layout epub requiring iBooks 3. I've noticed other books display an alert on launch requesting that users with an earlier version of iBooks upgrade. I can't find any information on how to implement this, and whether it's something that iBooks takes care of or some sort of custom Javascript code.
The following meta tags included in an epub exported from iBook Author looked promising, but in sideloading tests did not work. Of course, I'm just dropping these into the .opf of an epub created without books so it's possible there's something else that iBook Author is doing that makes this work.
<meta name="ibooks:requiredVersion" content="3"/>
<meta name="ibooks:currentVersion" content="3"/>
<meta property="ibooks:version">3.0</meta>
I looked into writing custom code, but Javascript alerts don't seem to work in iBooks. Any help would be greatly appreciated!
Javascript alerts do work in iBooks, although I'm not sure how you incorporate them into iBooks Author.
A script element in your
<HEAD>section will generate an alert:At worst you could probably manually edit the xhtml files iBA produces to insert this.