In these more environmentally concerned times, the car is often held up as being a major contributor to the grim climate change forecasts we are presented with on the news.

Whatever the car’s impact, it’s currently a very necessary tool in many people’s lives, with modern cities being designed around them and the commute a daily ritual for lots of workers keeping the wheels of the economy spinning.

Accepting that we’re not going to give up our cars anytime soon, we should at least aim to drive our them to their best efficiency and minimise their negative impacts.

Put simply, that means slowing down and driving more smoothly.

Doesn’t sound much fun, does it? Cars evoke freedom, the open road, and high speed is such a buzz. We need a way to make good, safe, efficient driving fun too.

Step in Flo - the smartphone app that gathers together data about your driving and turns it into a bit of a game.

Setup is simple. Sign up for a free account and tell the app what car you have. Presumably this helps calibrate the software to feedback the most accurate data possible.

Now fire up the app and drive! First thing to note is that in the settings you can have the app auto-detect when you start a trip. This is handy because you’ll no doubt forget from time to time and you certainly want to minimise using your phone whilst driving (in fact, leave it alone!).

If you have your phone connected to power, Flo is most enjoyable if you leave it on somewhere you can see it (it also needs to see the outside world for the GPS positioning). You’ll be presented with a simple dashboard that isn’t too distracting, but will feed you visual information about the quality of your driving supported by audio alerts.

Points are awarded for smooth driving. Don’t pull away from standstill too quickly or throw the car into corners and the points will start to accumulate. Get a bit aggressive and points will be deducted along with some angry beeps clearly indicating that Flo is disappointed in you.

I’ve been enjoying challenging myself to drive the car more smoothly and have seen the car’s own computer register an improvement in its MPG.

If this were all there were, I’d be inclined to suggest that it might get a bit boring a bit quickly - but there are some extras, both for the geeks and the social network fans.

The best way to keep Flo interesting is to convince a few friends to do it and compete with them. The 7 day scoreboard should be good for weeks of competition!

Geeks like me will also enjoy all the extra stats that the app serves up. You can review every trip and see your journey time and distance, your max and average speeds and a map view of the journey. You can even view a 3D visualisation of the journey, but this is a bit too geek even for me!

So a free app that can help you save the environment and a bit of money. Are there any problems with it?

Well, there is room for improvement here and there. Generally it’s a well produced app and the auto start means you should be okay to catch every trip, but the auto-start is part of the first problem.

What happens when I leave the phone on the living room table

Here’s an auto-start from when the phone was on the table in my living room. My guess is that the phone is picking up GPS satellites through the window and during the process of working out where it is, the app has jumped in and assumed a journey's started. Fortunately the so-called journeys are short and not recorded. They’re also easily deleted from the notifications.

The second problem I noted is that I cannot make a 90 degree turn without losing points. Seriously, my main car is a spongy family SUV and I can tiptoe round a bend only to be scolded as if I've just pulled an aggressive handbrake turn! This may vary from phone to phone and the accelerometer in my Samsung Note 3 could be at the root, but let me know in the comments if you’ve found the same.

Finally, I've seen a couple of occasions where the journey distance has been miscalculated. For example in the screenshot above, I drove from Whitley to Fleet - a distance of 22 miles, Flo thought it was 41!

I've done hundreds of journey’s with Flo installed though and this has been a very rare issue. The main thing is that I've been able to look at my time in the car and evaluate my use of the car, both in terms of frequency and driving efficiency. Better still, it’s been quite good fun, so I’m happy to recommend it.

What do you think? Would an app like Flo encourage you to drive more efficiently? Perhaps you’re already using it - have you seen a saving in the fuel bills? Let me know in the comments.

Thanks to Decos for supplying some pictures for this review