Dougal, being a iPhone 2G owner himself has recommended the following apps which work very well with other iPhones.They are all free and are categorized according to their productivity, networking capability, searching ability and the gaming style.
Evernote: this is a note taking app which lets you make text notes, photos, web page bookmarks, and voice notes.
Instapaper: Lets you bookmark a web page. When you sync it, it will save an offline version in the phone which can be read even without an Internet connection.
Night Stand: This app can replace your alarm clock and works with superb efficiency.
SnapTell: Takes a picture of your favourite item while shopping and this app opens the amazon page and tells you the price details.
Vlingo: This app enables you to give voice commands to your phone. Great for those users who find it waste of time typing the command.
DialX: This app needs a little practice, but once you learn how to use it, it lets you dial phone numbers without actually looking at the screen.
Stanza: This is a free e-book reader which provides a free built-in tool to let you bookies to download books legally.
Brightkite: this app is perfect for all those networking addicts, it will bring twitter, facebook and flickr into your hands.
Tweetdeck, Nambu, Twitterific, Tweetie , Hahlo, Twinkle: Tweetdeck can sync settings between your phone and your desktop version. Hahlo but an iPhone-optimized web interface. Twinkle is for location-based information search. Nambu, Twitterific and Tweetie are also Twitter clients with similar functions..
Facebook: This is an official facebook app and will be useful if you want to update or check your FB profile.
Weather Channel: reports the weather forecast
Shazam: it identify the artist and song that’s playing in your radio. And it will provide you convenient links to recognise the song.
Flixster Movies: provides all the information about the currently playing movies.
Sportacular: gives the up to date scores of any game that’s being played currently.
MovieStar: This app is the best iPhone interface to IMDBI , provides all the information about your favourite actors and latest gossip in the filmdom.
BubbleWrap: It’s a cute game which the kids love, it very much means what its supposed tp mean, pop the bubbles in the wrap.
Lightsaber Unleashed: Great game for all those who like adventure mixed with fun.
TapDefense: this is a tower defense game and is very much like its contemporaries but for the fact that its for free.
Koi Pond: this game is for people who want peaceful and happy games, you can shake the pond, have the fish nibble at your fingers and be contented just to watch it.