The iWatch is tethered to an iPhone and offers users a combination of health and fitness tracking along with various communications facilities such as messaging and e-mail. Three models of the iWatch are available including a sport edition and one made from 18-carat gold.
Bernstein Research analysts Toni Sacconghi estimated, ahead of the launch that if Apple were to sell 30m of the new devices at an average price of $250 it would add about $7,5bn to the company's coffers.
The new iWatch comes with sapphire glass, making it much more scratch-resistant and easier to use. However, the new iPhone 6 is not incorporating a similar feature, much to the disappointment of millions of users who listed the sapphire glass cover as being their number one priority for a new iPhone.
Analysts say the new iWatch is slender and more attractive than many of the other watches available on the market at the moment. It links to Apple's Health application and collects data about activity levels, sleeping, calories burned and pulse or heart rates along with exercise information.
Smartwatches are relatively commonplace with products already in the market from Samsung, Sony, LG Electronics, Qualcom, and Motorola.
Two models of the new iPhone 6 are available, one with a 4.7 inch screen and the other with an even bigger 5.5 inch one but will not have the sapphire glass covers, a disappointment for millions of users.
At the launch Chief Executive Tim Cook announced Apple's new mobile payment service, Apple Pay that will allow users to pay for items using their phone rather than a credit card. Apple Pay uses a secure element chip with a near-field communication antenna for this purpose.
