16 free iPhone apps you can't live without

For us, the launch of the iPhone 3G was less about the hardware tweak than it was about the App Store. Finally, Apple had opened up the iPhone platform to allow developers to create proper, native apps for the iPhone and iPod touch, and we couldn't wait to get installing.

The great thing about third-party apps is that you can do more than install them on an iPhone 3G; all first-generation iPhones can install them too, courtesy of the free 2.0 firmware upgrade. Even if you have an iPod touch you can get the 2.0 firmware upgrade, though it'll cost you £5.99. Some apps won't work on the touch, but that's usually only because they mandate a feature – speakers, mic, camera, GPS, say – that the iPod touch lacks.

Buying and installing apps is easy. You can browse or search the store through iTunes 7.7 or later on your Mac or PC, or use the App Store tool that you'll find on your iPhone itself. Apps bought in this latter way are backed up to your Mac at the next sync, and bug fixes and other upgrades are pushed through the iTunes Store ready for almost seamless updating. One weird thing with iPhone apps is that there's rarely a manual included. Some don't need it – they're so simple and intuitive – and some do it much better with pop-ups and other inline tips, but for a few the lack of a help system is annoying.

A final thing to note is that because the Push Notification Server – Apple's middle-man technology that will allow developers to push notifications directly to the iPhone, obviating the need for apps to run in the background – wasn't launched at the same time as the App Store, some of the apps that would benefit from it – Twitterific, NetNewsWire and Facebook, say – aren't as useful as they could be. What follows, then, is our pick from the applications available when the App Store launched. We've missed out a few of the very big hitters either because at the time of writing they were only available in the States, because they're designed for very niche groups, or simply because we thought others were more deserving of a spot in the limelight.

AIM

No iPhone-native version of iChat yet, but in the meantime this AOL IM client is very good. It's limited – you can only add one account, and it's restricted to AIM and .Mac/MobileMe sign-ins – but it's simple and slick. You can have multiple chats on the go at once, and any groups set up in iChat are replicated on the iPhone.

Facebook

Facebook's iPhone optimised website is one of the best around, so we had high hopes for the native application. It's certainly faster than the web app, and it feels slicker and more consistent with the iPhone's user interface. While the very first release lacked a few features that many regarded as essential – no way to write on walls, or see users' photos, things the web app were perfectly capable of – the quickly-released 1.1 version of the app added in these and more. There's a dedicated photo capture button that can upload your photos directly to Facebook, too, and of course you can now upload photos that you've taken previously. Once the Push Notification Server is rolled out, this will get even better, especially with Facebook Chat.