Among Apple's ( AAPL) 10,000 iPhone applications, there are dozens that can help you manage your money. They'll give you stock quotes and financial news, monitor your investment portfolios and bank accounts, and even place trades. Many of the best programs, including most of those discussed here, are free. Now you can compulsively track your finances any time, as long as you have a cell-phone signal. To download the applications, all you have to do is click the App Store icon on your phone's home screen. Why should you spend time downloading applications? Theoretically, you could use the phone's Web browser to visit sites directly. Trouble is, you might have to wait minutes for a site to load, only to find that its text and images aren't formatted for your phone. Here are six personal-finance applications worth checking out: iPhone's stock feature: iPhones come with a stock-search feature that provides quotes, charts and news. To browse recent articles about a company, click on its name. To change the list of stocks that appears on the application's homepage, touch the "i" in the lower-right corner of the screen, and then the "+" at the top-right corner or the "-" next to the company's name. To search for individual stocks, hit the "Y!" in the lower left corner for Yahoo's ( YHOO) "oneSearch" tool, and type the company's name or stock symbol into the search field. Bloomberg: This powerful, free application from the financial data company monitors stocks, streams news and offers interactive charts that can be viewed horizontally and vertically. In the application's markets section, users can touch an index to view its best- and worst-performing companies. Its interactive charts automatically expand to fit the screen when the phone is turned sideways. Bloomberg's Mystocks feature can track your portfolio, whether it's real or hypothetical.