Here are a few of the apps useful for Android that I found while searching the market for hours on end. I am a huge open source fan, I run Ubuntu Linux on my laptop and like trying out new software. One of the best tings about all of the apps that I am about to list is that they are all free, and they have a nice clean and professional looking GUI (which is a determining factor for me). So without further delay lets get this going.

Adobe Reader

Adobe has some great apps for Android, Adobe Reader and Mobile Photoshop, as I am sure that you all have heard Adobe is launching Adobe Flash support and an Adobe Air app for Android 2.2 codenamed Froyo. Adobe Reader is used to view PDF files on your mobile Android handset.

ColorNote

This is an excellent app for organization. Have you ever gotten somewhere and realized that you do not remember why you were going there in the first place? ColorNote is a great app to help you solve this. ColorNote allows you to make text pad notes or check lists so that you'll never forget to pay that bill or pick up that one thing that you were meaning to buy at the grocery market forever.

DroidLight

This is light . . . surprise! This app is actually pretty mainstream. A lot of people know about this app, but just in case if you haven't heard of this app I suggest trying it out. It uses LED for the flash on your camera and uses it as a flash light.

Finance

The Google finance app is great app for following the stock market and Watching stock. If you have invested in stock or are interested in investing in stock this is a great app to follow a company or the market on a whole.

LauncherPro Beta

This is a great home replacement app that allows you to have up to 7 home screens and customized app launcher tray at the bottom of the screen. If I had to choose only one app on this list of apps it would be this one. Keep in mind that this is a beta app however and does crash for a few seconds every now and then. I however have high expectations for this app and am looking forward to version 1.0. (The current development version released is 0.6.7.2)

Meebo IM

This is a pretty good app for connecting to multiple instant messenger accounts at a time, helping you to stay connected to your peoples even when your not at your computer.

Opera Mini 5 (beta)

This is a web browser app, I was mostly impressed by the smooth GUI that this app has. Keep in mind though that this app is still in beta phase so expect occasional crashes.

Pandora

If you like music then you will love Pandora Internet Radio. Pandora is an online Radio Service where you choose a song or an artist that you enjoy and Pandora will find similar songs and artist to what you have chosen. Even if you do not listen to music on your phone I suggest giving Pandora a try on your home computer at http://www.pandora.com.

Photoshop Mobile

As stated earlier this is an app made by adobe. Adobe Photoshop is an image manipulating program for Apple and Microsoft systems but now you can use it on the go. It is also important to mention that you do not have to have an Adobe account to use the mobile app but if you do want to use the online version you can go to https://www.photoshop.com/tools/ria?wf=organize and use your Adobe account information to use the free online version.

Ringdroid

Have you ever had a song that you wanted to set as a ringtone but it kinda had a lame beginning? With Ringdroid you can go through your media library on your phone and select where you want your ring tone to begin and save it as a ring tone.

Robo Defense

This is a fun strategy game. The purpose of the game is to stop units from making it through the defense that you set up. This is a surprisingly addictive game. There is a demo version and a full version, the full version isn't that much better than the trial version however there are some more units in the full version.

Runstar

Runstar allows you track your running time and other various stats using the GPS in your phone. With Runstar you can also set monthly goals for yourself. For more information watch this video:

Shazam

Has a song ever come on the radio that you did not know the name of and wanted to know what it was so that you could get it later? With Shazam you can "tag" songs that you hear and the app will search an online database to get that song and artist information.

World War

Another strategy game that allows you to control your army and fight other armies. there is a list of other apps that are similar by Storm8, the developers for "World War", ranging from "Vampires Live" to "iMobsters".