Each week Ross Rubin contributes Switched On, a column about consumer technology.

Often, a shotgun is used at the beginning of a dash, but not so in the world of connected GPS devices, where Telenav launched its Shotgun portable navigation device days after Dash decided to exit the hardware business with its pioneering Dash Express.

Unlike Dash, Telenav was no newcomer to the guided navigation space, being a leading provider of turn-by-turn navigation services to cell phones. Its customers include Sprint and AT&T, and consumers can subscribe to the service directly through Telenav -- even if their carrier doesn't support it -- as long as their smartphone does. The product is free to download, but carriers charge a subscription fee for unlimited use, or offer it on a per-diem price. Because it is designed for an inherently wireless device, Telenav software includes features such as traffic notification, which is a premium feature in portable navigation devices.

In addition to physical advantages such as the large screen, the Shotgun has at least one important advantage over Telenav's cell phone services. Since its maps are local, the device continues to route even when you drive outside of cellular coverage areas. But there's at least one holdover from its cellular heritage that Telenav needs to shed on the Shotgun -- an unceasing, bright blue LED signaling wireless connectivity, which is hugely distracting to the driver, especially at night. Perhaps a bundled strip of black duct tape will do in the meantime.

Despite the LED, based on the design of the hardware alone, the Shotgun would have been deemed a Dash Express-killer if the economy hadn't already beaten it to the murder scene. The Shotgun has a relatively slim profile in contrast to the Frankenstein-like flat head that crowns the Dash Express. Dash's user experience was very strong, and while the Shotgun's may not be quite as simple and is certainly not as extensible as Dash's, it is comparable to the generally good quality of user interface we see from Garmin and TomTom. It also avoids many of the frustrations of data entry precision in unconnected PNDs since, like the Dash, it can search for landmarks that may not be in its local point-of-interest database.

Dash won the hearts of early adopters with the ability to send custom RSS feeds to the unit. You'll see none of that esoteric functionality on the Shotgun, which has also eschewed WiFi for downloading large system software and map updates. Telenav says it has developed a way to do this efficiently without Wi-Fi, but is mum on how. On the other hand, the Shotgun's native "moving maps" mode mimics the "bird's eye" perspective more similar to the way most consumers use their GPS devices. Dash, in contrast, provided a flat 2D map so that you could see traffic trouble spots brewing on upcoming and surrounding roads. The Shotgun relies more on a proactive alert approach. The 2D maps are not missed per se, but it was nice to have an option of multiple routes on the Dash before venturing forth, even if they sometime involved minor detours.

At $299, the Shotgun hardware still commands a premium over rapidly falling PND prices and will have to face the same aversion to subscriptions in the PND market that surely hurt Dash. Also, while traffic is an easy feature to include in a PND, it is enormously challenging to do well given the near real-time notification required and intelligence to gauge the efficiency of alternative routes to be as effective as possible.

While traffic no doubt holds the most potential value for subscription services and could elevate PNDs from something used only occasionally to an everyday navigational tool, there are significant barriers to justifying the expense. It is probably of most use to regular commuters. It must be able to notify you early enough so that you can avoid he most crowded route. And it may be limited in how much time it can save you even if it delivers the optimal route when all main routes are congested, particularly on shorter trips.

This is why, for the near-term, it's going to be difficult to get consumers to pay in excess of $10 per month for such service and Navigon has seen its fortunes rise by promoting basic free traffic delivered via radio signals to its PNDs. However, for those who want the added convenience and flexibility of two-way communications in the wake of the Dash Express's demise, the Shotgun is a well-designed, effective and handy companion to have on the road. If backseat drivers are pestering you to pull over and ask for directions, there's no quicker path to passenger peacemaking than bellowing that one more request will result in your using your Shotgun.

Ross Rubin is director of industry analysis for consumer technology at market research and analysis firm The NPD Group. Views expressed in Switched On are his own.


Switched On: Riding Shotgun in a traffic jam