Vexia Econav 435 and 355 tested: Saving you petrol, in theory at least

It's been a long time since anything new happened in the world of sat-navs, but finally the day has arrived we can report on something different.

Spanish company Vexia is bringing its range of Econavs to our shores. The twist is that the sat-nav gives you advice on the most economical way to drive, telling you which gear you should be in and whether you're accelerating too quickly.

If you follow the Econav's nagging, Vexia claims it can save you between 15 and 30 per cent on your fuel bill, depending on your driving style and the number of miles you drive per year, based on the 16,000 people using its products in Spain.

It works by using the GPS signal to calculate both how fast you're driving and how quickly you're accelerating, alerting you if you go above the parameters it considers give you the best fuel economy. The advice it gives is tailored to fit your car -- select your model from the large pre-loaded database of vehicles when you switch it on, and it supposedly does the rest.

It also has a speed-camera database pre-loaded, so you should hear an audible alert if you start to drift above the speed limit, alongside the alerts for economy. Updates to the speed-camera database will be available in a couple of months for an as-yet-undecided fee.

So what's it like to use? In short, not great. We gave the Vexia 435 UK a trial run. It didn't have our particular car in its database, which is forgivable as it isn't a common flavour of Ford Fiesta, so we selected the closest we could find, a Ford Fiesta Ghia, which at least had the same engine, if not the right number of doors.

There are essentially two separate programs loaded on to the device, which you choose between at startup. The normal sat-nav app runs pretty much as expected (see picture below). You can put in postcodes to find your address, and there's a slightly irritating, but intelligible male voice to tell you which turnings to take. But this doesn't have any of the eco-driving messages, which seems like a huge missed opportunity. For those, you need to choose the Econav option at startup, which has no mapping functions at all -- it's intended to be used on routes you're already familiar with.

Choosing Econav was when the real problems started. No matter how hard we tried, we just couldn't make it work. Sometimes the program would appear to load successfully, then drop back to the startup menu with no explanation of what had gone wrong. Other times it would load, but wouldn't display any information about our driving performance, eco or otherwise. Pushing on-screen buttons here swiftly resulted in the sat-nav hanging, requiring a reset by jamming a paperclip into the side. Not something you want to be doing when driving. Or at all, come to think about it.

Menus feel quite sluggish -- the whole things runs on Windows CE Core 5.0, which might help explain the general tardiness. There's no Bluetooth for hands-free calling either, although that isn't unreasonable for the money.

Which brings us on to price. The Econav range isn't too expensive, but it's not cheap enough to overlook its shortcomings either. There are two models with 109mm (4.3-inch) screens: the 435 UK (with maps of UK and Ireland) costing £169 and the 435 Europe (with European ones) for £219. In October, Vexia will add two 89mm (3.5-inch) versions, the 355 UK at £135 and the 355 Europe for £169.

That might not sound too bad, but you can pick up a TomTom XL from Amazon with the same size screen, European maps and a pre-loaded speed-camera database for £150 -- £20 less than the Vexia 435 UK. Even assuming that the problems we had were either one-offs or something that will be quickly fixed with a software update, the Econav green driving program is essentially something that has been tacked on to what is at best a very ordinary sat-nav.

We leave you with a shot of the help screen you see when you first select the Econav application, complete with some Spanish we presume someone forgot to translate: