Fitbit, the world’s biggest fitness wearable manufacturer by units shipped, launched two new wristbands- Fitbit Charge 2 and Fitbit Flex 2.

Charge 2 and Flex 2 have added features on what Fitbit says are the most important health and fitness stats.

The firm claims both devices come with improvements including sleek new looks and a more engaging experience.

The Charge 2 device comes as a redesign of Fitbit Charge 2, with a more reader friendly display four times larger than its processor. The top features include; innovations from PurePulse, enhanced fitness experience, connected GPS, smarter and easier all-day tracking and much more.

Gabby Reece, American professional volleyball player, athlete, model, fitness leader and Fitbit ambassador said: “Fitbit Charge 2 is unique in that is gives me the tools and guidance. I not only have continuous visibility into my heart rate which gives me real insight into my overall health including workouts- but Fitbit built on that even further with access to my cardio fitness level.”

According to IDC, Fitbit continues to strive as ‘the undisputed leader in the wearables market’ topping Xiaomi, Apple, Garmin, Samsung and BBK with 24.5 percent in 1Q16 Market share and a total of 4.8 million unit shipments in Q1 2016.

Co-founder and CEO of Fitbit, James Park said: “Over the past nine years it has been our ability to innovate on both design and utility, and our deep understanding of what consumers want that has made us the leading global wearables company.”

In a statement the company said the flex device quickly became the best-selling tracker on the market, being one of the first wearables to successfully merge fitness and fashion, Flex 2 comes as a revolutionised device.

The Flex 2 is swim-proof, with the addition of more features all in as design that is 30% smaller than the original.

The Charge 2 and Flex 2 wearables are available for presale on the Fitbit website and various major retailers online, including Amazon.com.

Both devices will be made available globally at other retailers in September and October.