If you have an android phone you'll want to check out some cool apps in the android market place. Just go to the category of Business and you'll see a screen showing Top Paid and Top Free apps.
Starting with Top Free Apps
Documents to Go: Helps you carry all your excel and word documents. You will want to upgrade to the paid version for full functionality.
OpenOffice: If you don't like Microsoft you can use openoffice documents which is free. The only downside is you cannot open docx or xlsx files which you need Microsofts version. Most people don't use this anyways.
Box: This is a cool cloud storage hosting program. Great for working with clients. Also if you need clients to upload large files to you and don't want to do it through email use Box, also known as box.net and get the job done the best way.
Skype: You need this for your tablet or mobile phones. Important for messaging, video conferencing and screensharing.
Facebook: Great business app as long as you don't waste time on facebook. Also great app to use for conferences when all else fails.
LinkedIn: Another must have app for business men. This is also a useful messaging service.
Astrid Tasks: Get your tasks done with this app. The only downside is this app is too dark, on the upside maybe it saves more power.
Remember the Milk: Same thing as Astrid just different company for doing the same thing, marking down your to do lists and getting things done, as in GTD. This app is far easier on the eyes but they used to charge money to make it useful but they have since gone back on their deal so you can still use it functionally for free.
Looking for more android apps?