Well, I started with Laridian before smartphones, on a Dell Axim PDA. The nice thing about Laridian is that for the mobile devices the software is free, you pay for the books. But you only pay ONCE, so I was able to transfer all my books from the Dell Axim to the iPhone and then from iPhone to iPhone as I have upgraded. After all these years, I have a pretty good investment in Laridian books (Bibles, studies, maps, devotions, dictionaries, etc) so the OSX version is looking pretty sweet to me!