There is more to the car dock than just a plastic bracket and a suction cup. For starters, the dock is the only way to keep the Nuvi charged while in the car, as Garmin's decision to equip the 3790T with a Micro-USB port has made it impossible to directly connect the Mini-USB car charger. Additionally, closer inspection reveals that the dock features a speaker. When the Nuvi is docked and the power cable is plugged in, this more powerful loudspeaker takes over audio playback instead of the 3790T's space-saver speaker. The results are much more audible turn-by-turn directions and better quality for speakerphone calls. Finally, in order to save space internally, Garmin has elected to place the 3790T's FM traffic receiver inline on the power cable. This decision means that the Nuvi cannot receive traffic updates for routing unless it is placed in the dock and connected to power.
One of the most interesting features that the Nuvi 3790T offers is voice command. One could easily overlook this, because there is no voice command button located anywhere on the home or map screens. Instead, the Nuvi is always listening for preselected phrases to activate the voice command function. Simply say "Voice Command" and the Nuvi springs into action, ready to receive your instructions, all without the driver ever having to touch the device. By default, the activation phrase is "Voice Command," but you can change it to any string of words you'd like; for example, we set ours to "Hey, Garmin!"
The system is remarkably easy to use--once you realize that it's there--thanks to an onscreen display of available commands and spoken prompts. You never have to guess at what the Nuvi is expecting. In fact, we found it quite easy to enter most destinations without ever looking at the Garmin's screen. Of course, more-complicated street names, such as Divisadero, Tehama, or Embarcadero, are difficult for the voice command system to understand. In these cases, you can simply say "Spell name" and spell the street name aloud to input.
In addition to barking orders at the Nuvi, you can use the Nuvi with a Bluetooth-paired phone to talk to friends and family. Pairing can be initiated from the Nuvi or from the phone and confirmed with a PIN. Once paired, the 3790T acts as speakerphone, displaying caller ID information and prompting to answer or ignore when a call comes in. Additionally, a new Phone button is added to the Home screen. The system prompted us for phone book access when paired with our Motorola Droid, and after a few minutes of syncing, a Phone Book option was added to the Phone menu. You can also utilize the paired phone's voice-dialing function (if available), as the Nuvi's built-in Voice Command system doesn't seem to support the initiation of calls. Call quality is good, particularly when the Nuvi 3790T utilizes its car dock's loudspeaker.
We mentioned earlier that when the Garmin Nuvi 3790T is placed into its car dock with the power cable connected, the FM traffic function is activated. The Nuvi 3790T features lifetime traffic that is accessible on the main map screen as color-coded street highlights (green is low traffic, red indicates a jam) and icons, or in the traffic menu as a list of incidents. With a destination chosen, the traffic menu also gives you the option of listing only traffic along the selected route and updates the estimated time of arrival to reflect expected delays. The traffic service is free but ad-supported; text advertisements appear in the traffic menu or on the map during long periods of idling. Touching an ad brings up a listing of nearby locations for the advertiser, for example, Olive Garden or Best Western motels. We found the advertising model to be unobtrusive, but some people are bound to take issue with ads on a device they've paid almost $450 to own.
The Nuvi 3790T also has a set of features that helps drivers get from point A to B as efficiently as possible. Gathered under the ecoRoute option in the Tools menu is a collection of tools and tips, which help you to monitor and, in some cases, improve fuel economy. After inputting the car's city and highway fuel economy estimates and fuel costs, you can generate mileage reports and estimated fuel costs per trip. While driving, an ecoChallege icon on the map screen shows how greenly the vehicle is being driven with a score and color code (red to green, of course). When you stop to fill up, a function called At the Pump gives a place to punch in the current fuel price, amount of fuel used, and distance traveled to calculate actual miles per gallon. Interestingly, Garmin doesn't list the 3970T as compatible with its EcoRoute HD, despite its positioning as the flagship Nuvi unit.
Of course, before we pat the Nuvi 3970T on its brushed aluminum back for any of its gee-whiz features, it has to be able to get us from here to there without issue. Fortunately, the Nuvi seems to have the right stuff in this respect as well.
Garmin isn't a stranger to making strong-performing GPS devices, and the 3790T is no exception. Boot-up time takes about 20 seconds, but you are given the option to simply put the unit to sleep between uses for instantaneous booting. Cold boot satellite lock took about 60 seconds on the initial boot. Subsequent satellite acquisitions were nearly instantaneous depending on exposure to clear skies. Like all GPS devices we've tested, the narrow, skyscraper-lined urban canyons of downtown San Francisco's caused problems with maintaining a connection with the GPS satellites for positioning, but along wider roads lined with shorter buildings, the Nuvi 3790T maintained a hard lock on our position. Text-to-speech and graphic lane assist go a long way toward improving the quality of the directions received.
Between the good voice command system and the responsive onscreen keyboard, inputting a destination into the Nuvi 3970T is extremely easy. However, we'd like more options during destination entry regarding the sort of trip we're planning. As it stands, the options for trips that avoid or stick to highway, or fastest or shortest trips, are hidden away many levels deep in the Tools menu. We'd really like to make that choice when we confirm our destination.
Garmin has managed to cram nearly every trick in its book into the 3790T's svelte frame (with the exception of its nuLink data service; for that you'll have to check out the Nuvi 1690), but it has done so without making a cluttered mess of the interface. This top-of-the-line model remains as easy to use as the Garmin Nuvi 200, which started it all. For example, we like that the voice command system is truly hands-free, removing both the need for a voice prompt button and for undue driver distraction. Also, we love the 3790T's design. The slim profile and large, sharp screen make this Nuvi one of the most portable and best-looking standalone GPS devices that we've tested. Although we don't like the screen's glare in direct sunlight, we still think this device is worthy of an Editors' Choice Award.