If you’re only using your mobile phone to place calls, check e-mail or surf the Web, you’re not taking advantage of all it can do for you and your growing business.

Yep, just as it’s estimated we only use about 10 percent of our brains, you’re probably overlooking many -- if not most -- of your phone’s handy hidden features.

Here we explore a few business-related uses of your cell phone that you might not know about, or use.

Tethered modem

Can’t find a coffee shop to log online with your laptop while on the road? Rather than using Wi-Fi, many people are connecting their phone to their notebook computer to use it as a modem -- even while in the back of a taxi.

“Most newer phones offer this feature -- connecting it to your laptop with USB or Bluetooth so you can log online -- but not many people are doing it yet,” says Erez Zevulunov, director of MIT Consulting, a Toronto-based technology solutions firm. “And now with cell phone bandwidth rivaling broadband modems, such as with 3G phones, speed isn’t an issue anymore.”

Be sure to check with your carrier first to make sure your data plan covers this feature, and find out what the roaming charges are when out of town.

Backup data

Speaking of connecting your phone to a computer, you can carry around many if not all of your contacts and calendar appointments with you -- software is often provided by the phone manufacturer. Furthermore, it’s also a convenient way of protecting your PC files in case something happens to the machine, such as damage caused by fire, flood, theft, virus, or power surge.

Many phones today also offer expandable memory, such as a 2GB MicroSD card, which is enough to store thousands of documents, spreadsheets, and presentations. Make sure, however, to compress all of these files into a password-protected .zip or .rar file -- just in case you lose your phone.

“Productivity features usually depend on how ‘smart’ the phone is, such as those with an open operating system, but many basic, conventional phones have data back-up services to protect against information loss,” says Nathan Dyer, senior analyst for enterprise mobility at the Boston, Mass.-based Yankee Group.

Memo taking

Many entrepreneurs and small and mid-sized business owners come up with a great idea while on the go, but don’t have a quick way to document it before the epiphany is lost. Guess what -- your phone likely has recording functionality buried in one of those option menus.

“I know lawyers who have stand-alone digital recorders and I ask them ‘why bother?’” says Zevulunov. “You can easily dictate for an hour or more, especially with expandable memory cards, which you can then download to your PC to archive.”

Mobile phones are also ideal for recording boardroom meetings and important conversations.

Also consider the free Jott voice memo service. When you’re out and about and need to send a message to someone (or “jott” a note to yourself), simply call a toll-free number, say your message clearly, and your speech will be converted into text and then e-mailed and text-messaged to the recipient.

GPS navigation

“More and more phones have embedded GPS capabilities that are extremely useful for turn-by-turn directions and locating addresses,” says Dyer. As an example of the latter, if the important client you’re taking out for lunch has a yen for Japanese food, you can quickly find the nearest one with a couple of button presses.

In fact, cell phones with integrated GPS will likely be as common as a built-in camera. Increasingly popular services include TeleNav, which costs about $10 a month, and don’t forget phones like the iPhone offer Google Maps with satellite imagery.

“Even if your phone doesn’t have built-in GPS it probably has Bluetooth so you can pick up an inexpensive receiver to keep on your dashboard,” says Zevulunov.