Abstract: A double-sided keyboard comprises a rearward-facing keyboard, a traditional front-facing keyboard and a hinging means. The double-sided keyboard is assembled in a way that the rearward-facing keyboard is on one side of the double-sided keyboard while the traditional front-facing keyboard is on another side of the double-sided keyboard. The hinging means, being on one edge of the double-sided keyboard, is used for connecting to one edge of a tablet computer or mobile computing device, and further provides a sliding mechanism for guiding the sliding motion of the double-sided keyboard. When the double-sized keyboard is attached on to back of a mobile computing device, the rearward-facing keyboard is facing rearward away from the user as the user holds and faces the display screen of the mobile computing device, so that the fingers of the user are free to press the rearward-facing keys on the rearward-facing keyboard.

Abstract: A keyboard that is attached on to the back of a mobile computing device, having keys that are facing rearward away from the user as the user holds and faces the display screen of the mobile computing device. When the user holds the mobile computing device with both hands at the bottom or side edges, his/her fingers are free to press the rearward-facing keys of the attached keyboard. The keys are divided into one partial field for the left-hand fingers and another partial field for the right-hand fingers. The keys within their respective partial fields are placed in mirror-opposite of the positions that would have been in a front-facing keyboard that is laid before the user. This rearward-facing key orientation allows the user to use the same rapid typing system, such as that of the QWERTY keyboard layout, on the rearward-facing keyboard as he/she would on a traditional front-facing keyboard.

Abstract: A keyboard that is attached on to the back of a mobile computing device, having keys that are facing rearward away from the user as the user holds and faces the display screen of the mobile computing device. When the user holds the mobile computing device with both hands at the bottom or side edges, his/her fingers are free to press the rearward-facing keys of the attached keyboard. The keys are divided into one partial field for the left-hand fingers and another partial field for the right-hand fingers. The keys within their respective partial fields are placed in mirror-opposite of the positions that would have been in a front-facing keyboard that is laid before the user. This rearward-facing key orientation allows the user to use the same rapid typing system, such as that of the QWERTY keyboard layout, on the rearward-facing keyboard as he/she would on a traditional front-facing keyboard.