Of course you know there has to be additional costs somewhere and you would be correct, but it still works out relatively cheap especially when you consider the features on offer - which we will come to in a bit.

When you first get the product you need to activate the software via your mobile and then you are sent a link which includes the installation instructions. Installation does not take too much time but this depends if you have a 3G capable phone (as this speeds things up the downloads a touch).

Once your software is running you then get one months rights to download map content and updates to your phone, after the one month period has expired you either navigate on a PAYG system at a cost of 79p per trip or pay £5 a month or £50 for the year (which gives you unlimited trips, you just pay for data rates) to keep using the service.

The benefit of the download service is that you are only downloading parts of the maps that you need for each destination, but as data is transmitted before and during the route you are best to have a good data plan in place to start with, but the data costs can be reduced by selecting Economy mode and turning off advanced features such as safety camera alerts.

Having the routes transmitted to the phone on the fly allows you to fit the maps and the software on your phones internal memory, reducing the storage load associative with most SatNav systems, plus your maps and software is always kept up-to-date without you having to spend a large amount on update charges.

Features are actually quite impressive for a product of this price range, not only do you get TMC info, there’s a safety camera alert option, speed warning system and more impressively a text to speech function, which will speak the road names that you need to turn into, something which a lot of more expensive devices don’t provide.

To keep the costs down the interface has been simplified as much as possible, there are no fancy bells and whistles here, so inputting destinations has no auto fill function as you type and the menu colours are bland. But it does support 7 digit postcodes, address, POI and you can also send routes to your friends via SMS.

There are no route planners or simulation that we could find either, so it will limit its use to some degree but you do get a city map which allows you to search destinations in an A-Z style fashion - so you can see what the destination roads will look like before you arrive.

When you are ready to navigate it takes a little while for the route to be calculated and the map detail to be loaded, but this is faster depending if you are using 3G (as it has to download the data from the servers).

You get a choice of different map views during your travels but we ended up using the arrow system with info, this displays a large arrow in the middle of the screen with basic info at the base, such as distance to destinations and speed.

You can change map view and other settings for that matter using shortcut keys which was cool, but the other maps on offer - though more detailed - have no auto zoom facility (the reason for this is to reduce data charges) so you need to manually zoom into a map for them to be of any use, which will of course cost you more and takes time.

The lack of detail of the arrow and info system is made up for by the excellent text to speech option, which allows the unit to speak the road names that you are currently on and need to head to, at first it made the odd mistake when announcing the road names but this happened only once at the start, the more the device was used the more accurate it got.

This was also the case with route calculations, its efficiency seemed to improve the more it was used, possibly as data is cached into the phones memory it improved on performance, but considering it has to download changes on the fly, it actually re-calculates route reasonably quickly. We would not recommend straying off course too much though as this will all add up to the costs.

Picking up our location via the GPS receiver was a hit and miss affair, in closed spaces the acquisition time is poor, but thankfully in the open space, it got a location in seconds.

During our test routes the safety camera warning system worked a treat and the TMC option is also a bonus, interestingly you can even send traffic problems up to the server to share with other users.

At times the spoken directions are relentless, for example if you go the wrong way and continue going the wrong way it had the tendency to repeat 'please make a u-turn on such and such a road' over and over again until you do something about it.