I would have to say that for me the iPhone has become one of those transformational gadgets that has changed my life for the better. Probably the iPhone and GPS (SatNav for my EU friends) make the most impact on making my life better.
I thought I’d share with you the iPhone applications that have become ‘must have’ apps for me.
RadarScope

RadarScope is a specialized display utility for weather enthusiasts that allows you to browse NOAA’s public NEXRAD Level 3 data feed. It can display the latest base reflectivity, base velocity, and storm relative velocity data from any NEXRAD radar site in the lower 48 United States.
I love this application because it lets me have instant access to a full motion radar images when the skies look angry. This is especially helpful when I’m out on my motorcycle. I can instantly locate my position, pull up full motion radar and zoom way in to see if the storm is headed my way and going to get me. It’s also great when there are bad weather and tornado alerts around.
Tweetie

Of all the Twitter applications, Tweetie works the best for me. It allows me to easily maintain more than one Twitter account (yeah, you should be following me on @GetOutOfDebtGuy), uploads pictures to twitpic, shortens urls, follow and unfollow, etc. It is loaded with nearly every Twitter feature you would want and it runs well.
WiFiFoFum

AP Mobile News

There are lots of news applications out there but I like this one the best for its speed and incorporation of video news stories in its broad categorized listings. For example, if I want to read business or wacky news, I can read the latest stories and also watch the Associated Press videos on the iPhone as well.
iEarn

If you do anything with Google Adsense then you might be curious to see what your stats are. iEarn seems to do a good job for me because it’s simple and easy to use.
iEarn gives you a quick overview of your Google Adsense™ earnings. See your Google Adsense™ revenues made today, yesterday, the last seven days, this month and last month.
All you need to do is to enter your Google Adsense™ credentials at iEarn Settings view and press iEarn icon from your iPhone™. iEarn stores your credentials locally on your iPhone™. iEarn connects directly with Google Adsense™ using https.
No username, password or data are sent to any servers other than Google Adsense™ Web Server. The amounts are downloaded and displayed from the iPhone™ using the same web browser you use to browse pages from iPhone™.
iEarn in addition converts your earnings from USD to EUR,AUS,GBP,RUB,CAD with current exchange rates.
Newsdesk

Newsdesk is one of my most ‘go to’ applications on my iPhone. It easily gives me a look at the breaking or most important stories in news, tech, and entertainment. I have my app set to launch for tech news and to be honest that’s all I use it for. What makes this app so helpful is that it pulls from various good sources and you can easily launch the underlying source to read the news.
It took me a bit to learn how to really use the application but once I did, I love it. Tech news updates are frequent and contain a good smattering of reviews, breaking news, trends and discussions. For tech news, this is where I turn first.
iPod
The included iPod app on the iPhone is a must for me. I use it to listen to all my tunes when I’m out riding the motorcycle. With the iPod application on the iPhone, ships with it, I don’t need to carry an additional music device to listen to my tunes. In fact, with the iPod and camera built in to the iPhone I only need to carry one device to take photos, make calls, get my email, and listen to tunes.