Microsoft wants to put a second screen in the back of your phone. Plans spotted by Patent Bolt reveal that the folks behind Windows Phone have explored the possibility of putting an extra low-power display on the back of a phone or tablet.
The second display, controlled by a dedicated low-power processor, uses very little juice, so the rear screen could be on for longer than the main screen without caning the battery. It frees up space on the front screen for admin-type information like the time, and the strength of your battery and phone signal.
The second screen could also display logos or patterns, allowing you to change the look of your phone just as you change the wallpaper on the main screen. And it could wrap around the contours of the case, for an all-over cool look.
E-Ink is one suggestion for the second display. Common on ebook readers, the screens comprise tiny balls beneath the display that are light and one side and dark on the other, and each flip one way or the other to create the image. They're limited in the amount of detail and colour they can display, but use very little power and can be seen even in direct sunlight.
Microsoft filed for the patent -- like copyright for inventions -- at the end of 2010, and it's just been made public by the US patent office. Of course, Microsoft doesn't do much hardware, so it's unlikely that this will show up in a phone any time soon. Unless the patent is related to Microsoft's Windows Phone software, of course.
Bill Gates' mates aren't the only ones looking to do something with all that space on the back of a phone: the little-known but quirky O2 Cocoon sported a basic display on the back, which could alert you to text messages or, when docked in a cradle, become an alarm clock. And the Sony PlayStation Vita has a clever touchpad on the back.
Some of Samsung's compact cameras have a second screen on the front, so you can take self-portraits. Many moons ago, Windows Vista had a feature called SideShow, which allowed laptops to have a little screen in the lid that could do low-power tasks without booting up.
Apple has also patented a hybrid E-Ink and LCD display which could switch between low-power E-Ink and sophisticated touchscreen at a stroke.
Do you want a phone that has some gear in the rear? Or would an E-Ink screen be junk in the trunk? Tell me your thoughts in the comments or on our Facebook page.