I guess it would help if he's also American (don't know where he's from) so he could fight Apple on home turf and use the jury system on his side like "Evil megacorp steals from the little guy" (does it even work like this in the US or did I watch too many movies?), but I'm more curious how a lawsuit would go if he'd be in a jurisdiction different than the US.
Like, if for example, the author would be Russian, could he sue Apple's Russian legal entity and they would just shrug it off as "Yeah, that's not us who screwed you, go to the US and sue the Apple US HQ."?
As a non-lawyer I'm really curious how the legal system works for such disputes.