I suspect that Garmin has the market share lead for portable GPS, but I haven't seen the numbers so this is little more than a SWAG. I haven't chanced across one of their units yet, although I suspect they're all using the same basic technology.
Today I knew that we'd be in need of directions to Janice-Bob, so I decided to give the GPS in my cellphone a whirl. Rather than spend a few hundred dollars for a TomTom or a Garmin, why not try the VZ Navigator [VZN] to see if it would meet my needs (at $3/day or $10/month plus some airtime as explained in the FAQ) especially since all I had to do was download a BREW applet to my phone?
Aside: don't know how much airtime I consumed today (at weekend rates) since Verizon appears to have a 48-hour delay in statistics, when accessed from the phone.The verdict? I got mixed results. VZN found the first place (Poor Richard's Cafe in Plano) without breaking a sweat. Then, I gave it a specific street address (on Preston Road) in Plano and it found a different address in Frisco (inexplicably, a different location of the same automotive service chain). Since the locations were 5+ miles apart, this was less than inspiring.
When I tried to search by business name, it found many other locations, but not the one I sought. Is the Achilles' Heel the typical GIGO problem (Garbage In, Garbage Out)? Trying to maintain an updated database of retailers - who come and go as the wind changes - is a difficult task.
At our next stop - a clothing store chain - we found an empty store* (I suspect there was a location of this retailer at one time, but the location had long-since closed). Fortunately, there was another one a few miles away, so by then we'd turned off the VZ Navigator (rapidly sucking the battery) and were locating by sight.
After JB dropped me off, I had an errand of my own to run .. only about 3 miles away. I thought I'd amuse myself and see how well it performed this task .. and the results weren't stellar. First, it had a lot of trouble figuring out my location, having to reorient itself a dozen or more times. I suspect it's trying to use cellphone towers to triangulate my location rather than a GPS satellite (!) so I may have been at the mercy of the cellphone network. It seemed to do okay on the freeways, but bogged down when there were lots of small streets nearby. Pre-trip planning seems to be an appropriate part of using this service.
Part of VZ Navigator involves displaying only a local map, and it did a credible job (given the small screen on my cellphone). The voice prompts were nice, although it'd be nice to shut the speaker off when desired - there's no obvious way).
Also, the [Recent Searches] menu doesn't allow individual entries to be cleared, which is annoying .. mine rapidly piled up with bad locations.
Bottom line: VZ Navigator's handy, but not trustworthy .. I'd grade it a C+/B- overall. I'd rather have access to Yahoo! Maps, which gives step-by-step directions. Yet, VZN downloads maps as needed, so any wrong turns could be corrected quickly. And certainly, in a unfamiliar city, it's more useful than stopping at a gas station every mile to ask directions, fer sher. I'd also compare it favorably to the Hertz
Details, if anyone's interested:
phone: Motorola V325 (software R9.1_X_05.28.09P)
VZ Navigator 2.8.1 Build 40
* if this has been a trip with Jill Wazabob, finding an empty location would be the expectation, not a surprise.