Amazon is planning to launch a device that plugs into smartphones and tablets so that they can be used to validate card payments.

9to5Mac has managed to get its hands on a set of internal documents from US retail giant Staples that detail an Amazon Card Reader that will go on sale starting on August 12 and that it is going to be selling for $9.99.

Rarlier this month, Amazon quietly launched a mobile wallet app that is compatible with Android smartphones as well as Amazon’s own devices.

It can currently be used for storing gift cards, membership and loyalty cards; just scan them via a phone’s camera and they’re loaded into the virtual wallet. However, the app doesn’t support credit or debit cards, yet.

The launch of a credit card reader that plugs into a smartphone or tablet could change all of that.

Mobile payments is struggling to win consumers over despite some very big tech companies, including Google, already offering the service.

So far, the only companies that do seem to be making progress are Square and PayPal. Both companies offer plug-in dongles that can be used for making credit card payments supported by apps that allow consumers to make small-value mobile payments at places that use the readers.

This is a feature that has proved very popular among Starbucks customers in the US since the coffee shop chain adopted the Square card reader in 2012.

The discovery of the Amazon card reader documents comes just a week after a report from The Information claiming that Apple is also finally ready to enter the mobile payments space.

Its sources say that the next iPhone, expected to be launched in September, will offer a mobile wallet function and that Apple is currently in heated discussions with a host of major payment industry players to finalize details.