Apple's first smart watch Apple Watch has already received nearly one million pre-orders on the first day in the USA.

The technology giant launched the pre-order period last Thursday, but large amount of orders and an insufficient number of products forced many of the models to go out of stock for months.

Many users have already put the smart watches they bought on sale on online shopping platforms for nearly twice what they paid.

While Apple will sell the 42 mm Apple Watch Sport for $399, the same watch has been put on sale for $700 elsewhere. Similarly, another Apple Watch model, which is estimated to be $699, is also being sold at $1000.

The Independent said that most customers had pre-ordered their Watches in Apple's "space gray" aluminum cases, which represented 40 percent of pre-orders.