(Pocket-lint) - Sony has announced a second generation activity and fitness tracker that maintains the core design and abilities of its first, but adds a heart rate tracker to more accurately judge pulse and cardio information.

The Sony SmartBand 2 looks almost identical to its predecessor, but the module under the wristband now contains a biometric sensor to read a wearer's heart rate.

Its information is sent to the Lifelog smartphone application (for Android or iOS) as before, but it has also been updated to be able to read the heart rate data and therefore better gauge overall fitness, excitement and stress levels.

In addition, the band has an accurate pedometer to track steps - which we praised in our review of the first model - and there is sleep detection too, with the SmartBand 2 designed to be comfortable enough to wear twenty four hours a day, seven days a week.

READ: Best fitness trackers: The best activity bands to buy today

Like the original, the SmartBand 2 can also alert you when you have a call, message, email or tweet through vibration and pulsing LEDs on the strap. You can also use the band to play, pause or skip through music tracks playing through a phone or tablet.

And it will alert you when you've strayed too far from either.

Its battery life is claimed to last up to two days and the device can be fully charged in around one hour. It will be available globally from September in four colours: black, white, pink and blue. Price is yet to be revealed.

Writing by Rik Henderson.