The I Love Potty Training app included a potty training book for boys and a separate one for girls, there is also a potty training game, advice and help for parents and a sticker chart. This is a mammoth sized iPhone app which is best downloaded and synced with your computer.
If like me, you want to try both apps to keep your potty training child interested you can download both for less than one printed potty training book.
As a side note, this means that I have had to relinquish control of my iPhone to my kid while he uses the potty. No accidents with it so far – touch wood – but I keep Lysol in hand for a quick de-germify after.