The proliferation of touchscreen technology revolutionized mobile computer input, even for those who can't see what's on the screen. In addition to existing VoiceOver and Accessibility features, blind iPad users now have a new app for typing on its display.

iBrailler Notes, which began as a summer project at Stanford University in 2011 and is now available as a stand-alone app for iOS, aims to offer blind and vision-impaired iPad users an easy way to type Braille notes and perform basic word processing on a touchscreen.

iBrailler isn’t the first to undertake this commercially. There are a variety of apps designed for the sight-handicapped, ranging from camera applications that describe the content of an image aurally to other Braille-reading and writing apps. Add to these the numerous accessibility features Apple offers on iOS, most notably VoiceOver, which reads text aloud to sight-impaired users, and its Braille QWERTY keyboard.

What iBrailler does differently is position its touch keyboard underneath the user’s fingertips, no matter where they set them on the iPad’s slick glass display. Every time you lift and readjust your hands on the screen, the keyboard does too. The keyboard uses Braille English Grade 1, Grade 2, and Six-Dot Computer Braille, and features built-in gestures for tasks like cutting, copying, and pasting text.

More than 6.6 million Americans over the age of 16 are visually impaired, according to estimates by The National Federation of the Blind. Much of that number are able to use computers thanks to the tactile feedback of a keyboard, optionally with raised Braille lettering on top, or a refreshing Braille display.

But a refreshing Braille display can be very expensive—thousands of dollars per unit, according to Ed Summers, a blind computer scientist with business analytics software firm SAS. A Braille keyboard is very different from a QWERTY keyboard, he tells me: eight keys, one for each dot that can compose a Braille letter, and a "display," a strip of 18 to 80 Braille cells, each housing eight tiny pins that raise to form a letter. Using this, a blind person can type on an iPad (or computer screen), moving the cursor around, reading text, correcting spelling. A small, 18-cell Braille keyboard can run around $1,800, while larger ones can cost in the realm of $6,000.

Sohan Dharmarajah, one of iBrailler Notes’ creators, wanted to offer the benefits of such a keyboard at a more affordable price. This iOS app is a free download from the App Store, and users can subscribe for a small monthly fee if they like the experience and want additional features.

Summers thinks that an app like this could be incredibly useful, particularly for students (he works with teachers of blind students in addition to his science work). Historically, he says, visually impaired students have had to use tools that make them stick out like a sore thumb in class.

"Now they can use an iPad and they’re the cool kid," he says. "They have the coolest technology in the classroom." Summers also notes that this keyboard app could allow blind users to type incredibly quickly.

The app's creators aren't entirely sure how big the Braille iPad-user market is—certainly a growing number are used in education, and since the iPad was completely accessible to the blind from the get-go thanks to VoiceOver, Apple fans of any sight ability have been able to use it just fine. But actually typing out thoughts with your fingers, rather than dictating with your voice, was still prohibitive.

Dharmarajah says feedback for iBrailler Notes thus far has been overwhelmingly positive; the app is being used actively at several blind schools and institutes in the United States and in Sri Lanka. An Android version is also in the works and should be available soon.