US Patent and Trademark Office

While a tablet's front touchscreen allows users to complete thousands of different tasks, the back of the device doesn't typically do much.

Apple may want to change that, making the back of its iPad tablet much more functional with sensors and controls across its surface. The concept was mentioned in a patent the US Patent and Trademark Office approved for Apple on Tuesday, which considered sensors positioned in lines or a grid across the back of a tablet.

The concept could open a tablet up to new uses, such as more complex games. For now, a lot of mobile games only involve tapping and swiping, since most mobile devices don't have separate physical controllers. Providing a set of new controls on the back of a tablet could allow for games that come closer to play on a console.

Also, Apple is currently struggling with softer sales of its iPad, the company's second-biggest moneymaker, so a new feature like a functional back might help boost demand.

The patent mentions that sensors could be ultrasonic, pressure or capacitive sensors, and the sensed position of a user's hands could either be shown on the front display or not, depending on different uses.

The same patent also mentioned a possible way users can avoid looking down to type on a keyboard, suggesting a virtual keyboard could be shown on a monitor to allow someone to see what they are typing.

An Apple representative didn't immediately respond to a request for comment.