Simon Caulkin writes: "One lesson is the importance of using the right medium, and executing it properly. The iPod is a textbook example of getting applications - for playing, organising and buying music - to work seamlessly together through the net without dropping you between the gaps. The second is simplicity. The more complicated the product, the harder it has to work to make you love it. A large part of the iPod's appeal is how easy it is to use - put another way, the fact that nothing gets between you and what you want from it."