The new Jawbone Up24 might look just like original Up but there’s one major difference: Bluetooth. See also: 10 Best activity trackers of 2014.

Instead of plugging the band into your smartphone's headphone jack, the new version can synch wirelessly all day long. As long as you have a compatible smartphone, that is. You’ll need an iPhone 4S or later, or one of a handful of Android devices.

In just about every other respect nothing has changed. There’s a subtly different pattern in the rubber, and you have a choice of black, orange, pink or green.

There are three sizes, and it's important to buy the one that will best fit your wrist. The new packaging even has a sizing guide so you can check before you buy.

The UP24 tracks exactly the same things as the old model: steps, distance, calories and sleep. There's still no altimeter for measuring stairs climbed nor a heart-rate sensor, but all the important stuff is covered, and what the band does, it does well.

Jawbone UP24 review: Features

There’s just button which can be used for various things: a short press tells you the current mode, a long press switches between awake and sleep modes.

A quick tap and hold starts the stopwatch, while a double-tap and hold starts ‘power nap’ mode – the band will let you sleep for up to 45 minutes, and wake you at the optimal time using the built-in vibration motor.

Those same vibrations can be used for your morning alarm, as well as for idle alerts – motivating you to be more active.

Via the app you can configure all the band’s settings including multiple alarms and when you want idle alerts.

We like the app a lot. Large bars clearly show whether you hit your sleep and step goals.

You can tap on a bar to get more detailed information, such as how long you’ve been active and idle, your active calorie burn and more.

Sleep tracking is particularly good. The graph shows how much deep sleep you got as opposed to less valuable light sleep.

It's easy to change your sleep and steps goals in the app and you can also see charts of your sleep and steps over previous days, weeks and months. There’s also a Team section where you can compete with Jawbone-owning friends.

It's possible to keep track of your food and drink intake, with a built-in barcode scanner for processed food and an easy-to-use database for common foods and beverages. Of course, if you prefer, you can use a number of other apps which work with Jawbone’s app, from the ever-popular MyFitnessPal to sports-specific apps such as Strava and RunKeeper.

Although the Up24 is water resistant, it isn’t waterproof. You can wear it in the shower, or in the rain, but not while swimming or in the bath.

The battery lasts about a week, but it’s a bit of a shame that you still need a proprietary USB adaptor, which is easily lost. As the jack is now a 2.5mm version you can’t sync the Up24 via a smartphone’s headphone jack.

One thing we don’t like about the Up24 is the lack of a display. This means you need to fire up the app to check stats, and unlike other trackers, it doesn’t double as a watch.

Jawbone UP24: Verdict

If you can afford it, the Jawbone Up24 is a great activity tracker. It doesn't have the most features - and the lack of a display is frustrating - but as a tool for motivating you to exercise and generally live a healthier lifestyle, it can be very effective. Although the app isn’t quite as polished, the similar Fitbit Flex costs only £80, and is a better-value choice for most people.