It was probably only in this past decade in which people coined the phrase “desktop replacement” when referring to a laptop computer replacing a home computer, whether it be Mac or PC. Today, we can look at the term desktop replacement in an even different way. More and more I find myself using my iPhone to do tasks that I would normally do on my home PC or Macbook Pro. There are several different reasons that certain iPhone apps allow me to do this: Slick UI design, equivalent or better functionality to Mac or PC counterparts, convenience, the power of the iPhone 3gs (this article is based on the iPhone 3gs), and portability just to name a handful.

5. Facebook

I’m sure many of you spend countless hours on Facebook reconnecting with old friends and playing Mafia Wars. If you’re like me, you also use Facebook to share pics, videos, and Twitter-like updates with friends and family. Since I personally do not partake in the “fun” of Facebook gaming, the Facebook app for iPhone is all I would ever need to stay connected to the site.

From within this app you can check out your news feed, set people as favorites for quick checking, and see your latest notifications. I’m sure if you had to give up Facebook on a desktop computer, you could surely get by with this app, which happens to be one of the most popular iPhone apps out there.

4. Evernote

Evernote is my “getting things done” solution of choice. I also use it to take notes about everything from grocery lists to blog post ideas. In this particular case, all of my Evernote content lies in the cloud. If I go to the grocery store, I can bring up my grocery list and shop away. The Evernote app for iPhone supports voice notes, syncs everything back to the cloud, and includes landscape mode. For an app that needs to perform as a text editor that saves to a network space, Evernote does that and also includes some other treats.

Evernote for iPhone suffered from some seriously flawed releases when it was first launched, but through several frequent updates, they seem to have gotten many things right. So much so, that I rarely use Evernote on any other platform.

3. iReddit

Browse to the Reddit website on a desktop browser and it can seem a tad overwhelming. iReddit, which has had some seriously fantastic updates since its inception, brings it all together in a tight iPhone app. It really is the only way I ever read Reddit. This app comes complete with an interface that makes you think the Reddit website was made for this app and not the other way around.

Reddit has a great “pics” section. While it does not yet have the ability to save pics directly in the app, just tap the option to open in Safari and you are seconds away from sharing your pic with Twitter, Email, MMS, or IM. The Reddit app also integrates with all of the features on the Reddit site you would expect like voting, comments, and categories. It also has Instapaper integration. This app has a few things it could add in the future like the ability to make a submission, but as it stands now, this app is the only way I experience Reddit period.

2. BeeJive IM

While I cannot fully get away from instant messaging on the desktop during the day, my BeeJive IM app is always connected sending me push notifications for every IM sent to me whether it be a duplicate or not. This allows for a level of being connected that I’m not even sure I like. If I walk away from my desk at work to get a coffee or use the restroom, I’ll get the IM on my iPhone instantaneously.

This app has other great features like optional email notifications, landscape mode, color and background customization, chatroom capabilties, and even file transfers. When I look at desktop IM clients like Adium (Mac), iChat (Mac), Pidgin (PC), and Trillian Astra (PC), they are all “good enough”, but BeeJive has a look, feel, and functionality that has no match to date on the iPhone or the desktop.

1. Tweetie 2

I also use Tweetie for the Mac, but even that client is no match for Tweetie 2 for iPhone. With its innovative and natural pull down to refresh feature ( I find myself pulling down to refresh in other apps. Woops.), fast and clean interface, numerous integrations, and just flat out super performance, I find myself tweeting more from Tweetie 2 on my iPhone than any other platform available.

I would consider Tweetie 2 a true power tool. Retweet, saved searches, follow checking, and profile editing is all standard fare here.

So there you have it. The amount of things you can do with the power of something like an iPhone are becoming more and more impressive and abundant. For a modern geek like myself, this is a dream come true.

So what about you? Do you find yourself doing more and more “out of your pocket”? What are some iPhone apps you would consider desktop replacements?

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