The marriage between the cell phone and the PDA has resulted in the smartphone, a wireless productivity tool that many businesses can't live without. In fact, many consumers are also addicted to smartphones, relying on them for wireless e-mail and on-the-go Web access. But with a new model coming out (what feels like) each week, different form factors, and tons of new features, choosing the right smartphone can be overwhelming. If you're an IT manager looking to equip your workers with one of these, here's some advice to make the process a little easier.

1. Form factor is everything. Don't just settle on a smartphone and mass distribute it to your workers. Chances are many of them will come back complaining about the bulky design, uncomfortable scroll wheel, or way-too-sensitive touch screen that takes them places they don't want to go. Allow people to test out several smartphones, and then buy the one that gets the most positive responses.

2. Don't forgo voice quality. Many smartphones started out as PDAs for data entry and Internet browsing and had phone capabilities added to them later. When the BlackBerry was introduced in 1999, for example, it was strictly an e-mail pager. Often smartphone voice quality is worse than that of a standard cell phone, so make sure you get one that works well as a phone and as a data device. Nokia and Motorola both claim their latest smartphones (Nokia E62 and Moto Q, respectively) offer great voice quality. That's their specialty after all, being the top two cell phone makers in the world.

3. Dated technology can be a drag. The majority of the newer smartphones come with technology that supports third-generation high-speed broadband networks offered by major cellular carriers in the United States. This allows traveling workers to browse the Internet, access business applications, and download files at relatively fast speeds. Older smartphones like the Treo 650 work with older cellular technologies, so look for smartphones that support EDGE (offered by Cingular) or EV-DO (offered by Sprint and Verizon Wireless).

4. Put the bat down. Sometimes it's just easier to smash these devices and not have to deal with memory leaks or drained batteries that give out on you at the most critical moments. But that may not be the best way to deal with a device you've just spent $200 to $400 on. Pay careful attention to specifications and get a smartphone that offers a longer battery life. Make sure it also has expandable memory that will allow you to store more information.

5. Security, security, security. If you're serious about protecting data that passes between the company network and workers' smartphones, make sure you go to vendors like Research In Motion with a long history of including robust security features with their smartphones. Be careful about allowing people to buy their own smartphones. Consumer retail stores often don't include the necessary security and management software on smartphones they sell.

Am I missing anything? If you have other suggestions, please let us know. Or take a poll and tell us what the most frustrating thing about smartphones is. The shortcomings are plenty, so it's your chance to vent.