OK, so not everyone has one of Sonos' superb multi-room audio systems, but if you are one of the lucky ones then this app is a must have. It turns your iPhone into a fully fledged controller for your Sonos setup enabling you to control all the different zones around your home over Wi-Fi. The fact that it's completely free also makes a bit of a mockery of Sonos' £280 asking price for the standard system controller.
Unlike all the other entries listed here, Kizoom is an old school, web application like the ones that were all the rage before the App Store first made it's appearance. Kizoom is still worth having in your bookmarks because it provides an iPhone-friendly interface when you need to look up train times and check arrivals or departures. We know National Rail has improved its website, but we still think Kizoom is easier and faster to use on the iPhone.
Interest in eBooks really picked up last year with the launch of dedicated reading devices from the likes of Amazon and Sony. However, with this application you can turn your iPhone into an eBook reader for free! Stanza also gives you direct access to a number of book stores where you can buy and download the latest titles, but you can also access free book depositories like the Gothenburg project where you can grab yourself loads of free out of copyright classics from the likes of Mark Twain, Lewis Carroll and Willy Shakespeare. The interface is very easy to use and while the iPhone's screen isn't as good for reading as the e-ink displays used on proper eBooks, it's still very usable.
Bored? Frustrated? Don't start drumming your fingers on the table, start drumming them on your iPhone with this cool little application that offers up two drum kits - one acoustic, one electronic - that you can bash away at using your pinkies. You can even drum along the tunes stored on your iPhone. Just start a tune playing in the iPod app and then load up FreeDrumPad and play along. It's hardly an essential app, but it's fun nonetheless.