DIY: Mobile phones for your business

Thanks to number portability, you're no longer locked in to a particular mobile network provider, and can choose the right phone based strictly on design, features and service. Here are some of the key features to look for.

Long battery life is essential. Look for phones that use a lithium-ion (Li-ion) battery rather than a nickel-metal-hydride (NiMH) one. Li-ion batteries weigh less and provide 10 to 20 percent better performance than their NiMH counterparts. You'll want a phone with a rated talk time of at least 3.5 hours, preferably closer to 5 hours. If your mobile comes with a desktop charger, shell out for the travel charger since it's significantly smaller and easier to pack for business trips.

If your travels take you overseas, you'll want a tri-band GSM (Global System for Mobile communications) phone, which operates on networks (GSM 800/1800/1900) in Europe, Asia and the US.

You'll also want a handset that features a hefty address book -- at least 300 names with support for multiple entries per contact. Some phones allow you to include information such as email, Web and street addresses with your contacts. You can enter all that information one key at a time, or you can get a phone with the ability to synchronise with Microsoft's Outlook on your PC. Also making inroads in this area is SyncML, an open standard that establishes a common language for synchronising information between mobile devices and other computing equipment.

Among other features, check to make sure the phone you want supports conference calling, just in case you have to conduct an emergency meeting while you're on the road. You'll also be hearing a lot more about two-way, walkie-talkie-style communication in the near future. This technology -- also known as Push To Talk -- was pioneered in the US by Nextel. The company's Group Connect service lets you establish 200 groups with up to 25 members in each group -- a good option for instantly reaching your employees or co-workers. In Australia, Telstra is the only network operator to have announced a PTT service so far.

Because you never know if you'll need Internet access in a pinch, it's a good idea to purchase a phone that can connect to your notebook as a modem. You'll need to invest in the proper software and cables and make sure that your notebook can support such a connection. Or you can skip the wires altogether and get a Bluetooth-enabled mobile phone. If your PC or handheld doesn't feature integrated Bluetooth support, you can purchase an adapter to add this functionality. Then you can browse the Internet using your phone as a wireless modem; you can also use Bluetooth to synchronise phone numbers and addresses between your phone and other devices.

Even better, skip your notebook altogether. Fast Internet access is rapidly becoming a common feature in mobile phones. Most GSM phones support GPRS (General Packet Radio Service) networks, which offer always-on Internet content and data services, enabling access to Web browsing, email and multimedia content at around 56Kbps. On the horizon is a technology called EDGE (Enhanced Data GSM Environment), designed to provide data transfer over existing GSM networks up to three times faster than GPRS. If you want maximum mobile data speed, you'll need to opt for 3G, at up to 384Kbps. Hutchison is the only operator in Australia to offer 3G data right now, via its 3 service, but Vodafone is likely to follow next year.

If you spend most of your time away from the office meeting with clients, you may want to consider a smart phone, which combines mobile phone and handheld functions in one unit. These phones are larger and much more expensive than standard handsets, often costing as much AU$1,500, but they eliminate the need for two separate devices. Smart phones are available on the Windows Mobile, Palm, Symbian and BlackBerry platforms.

ZDNet Australia's Jeremy Roche contributed to this guide.