If you use SMS texting, Twitter, Facebook or other social networking sites, then chances are you do regular status updates. While it's fun to do the occasional emoticon 
you can take it to the next level with Feathers.
Feathers allows you to turn your plain status messages into something more interesting
The App is simple to use. Just key in your message and then choose a style for it. You can even do upside down text. Once you've styled your text you can send it straight to Twitter. You can also copy the styled text and paste it into other apps. How does this work? Are there special fonts at work here? Nope! That's the beauty of it. It uses standard unicode characters and that's why you can use the text in just about any application.
☺ sʇǝǝʍʇ ɹnoʎ ɥʇıʍ unɟ ǝɯos ǝʌɐɥ
You can get Feathers here:
As a frequent traveler there are times where I have no connectivity to the internet. As much progress is being made to equip planes with WiFi, I have yet to be on one that actually has a WiFi connection. Although I have a really good RSS reader on my iPhone that can cache my favorite sites, there are times when I run across articles on the web that are not in my regular feeds. These are articles of interest that I may not have the time to read right then and there. Luckily there's an App for that.
DataViz has long been in the business of allow you to take your documents with you on your mobile devices. So when Apple opened the iPhone and iPod touch up to third party developers, all Office document creators turned their eyes towards DavaViz in hopes that they would bring their Documents To Go product to the iPhone platform. Of course they did, and they did it in a good way. As much as I try to avoid MS Office documents as much as possible they are a part of the business world. I do get documents that I need to edit and provide feedback on. Just the other day a partner sent me a spreadsheet with speaking slots for Photoshop World and I needed to pick a time and add my name to it. Now I can do all of that directly from my iPhone.
Tracking time on a daily basis? In my work as a web designer, tracking time that I spend on projects, traveling for clients as well keeping together all financial items in a project, is vital. On the Mac, I have long been a user of Billings, by Marketcircle. They have made an iPhone version of the app available, that also syncs with the Mac version.
Tracking your expenses can benefit your financial planning, however it is hard to remember to save receipts for the smaller purchases you make where you perhaps do not use a card to pay. Pennies is an app that aims to help you track your expenses.