Even though Apple has yet to show off turn-by-turn directions on the GPS-enabled iPhone, navigation is one of the fastest-growing categories of mobile devices apps. As comScore recently noted, map use on cell phones in the U.S. during the three-month period ended May 31 was up 82 percent over the same period last year.

The demand is particularly high for step-by-step pedestrian navigation. GPS makers are responding by getting their services onto phones or, in some, cases, making phones around their services.

TomTom, based out of the Netherlands, deployed its Navigator 6 software at the end of 2006 on a wide array of handsets including models from Nokia, HP and Palm and included a Bluetooth GPS receiver to allow phones with no GPS chip to use the service. Intrepid TomTom-ers say they’ve even gotten it to connect to their BlackBerrys. And although it hasn’t yet been approved by Apple to be sold in the company’s App Store, the GPS maker has already gotten its service to run on the new iPhone. “We have made our navigation system run on the iPhone; it looks good and works very well,” a TomTom spokesperson wrote us in a statement. “We will have to look more closely to Apple’s strategy before we can say more about what kind of opportunities this will bring us.”

Meanwhile GPS veteran Garmin started offering its navigation software for the likes of BlackBerry and other smartphones last year. Garmin’s service even works with phones that don’t have native GPS by including an SD card-sized GPS unit that plugs right in.

In addition to offering its navigation services on third-party handsets, Garmin is developing its own hotly anticipated device, the nüvifone, a touch-screen smartphone with built-in GPS. But the company’s stock recently tumbled almost 22 percent to a fresh 52-week low after reporting second-quarter earnings that fell short of analysts’ estimates and pushing back the nüvifone’s release to the first half of 2009 from the end of 2008. Garmin says it’s waiting to launch the device with a mobile carrier signed on to provide service, which could help make the phone more affordable if that service provider kicks in to cover some of the upfront cost, just as AT&T has subsidized the iPhone 3G. Garmin’s units are often pricey; the nüvi 880 is nearly $1,100.

But the mobile phone market is a notoriously tough nut to crack and Garmin’s decision to make its own phone is very risky. TomTom’s strategy of getting its service onto as many third-party devices as possible seems like a far safer bet. And until Apple figures out what it wants to do in terms of navigation, iPhone users will have to make do with Google Maps.

image courtesy of Garmin

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