KNFB Reader Quick Start Guide

Accessible Devices has added HTML Headings and Paragraph coding to facilitate navigation.

Quick Start KNFB Reader iOS app knfb-website.png
logo sensotec rgb copy.jpg


Welcome to the world of rapid efficient text recognition and reading with our life changing KNFB Reader iPhone app. The KNFBReader app is capable of reading a wide variety of document types you may encounter throughout the day. It performs particularly well for reading printed memos, reports, fliers, and virtually any other kind of document typically printed from a personal computer.

It will also read many professionally printed items of various sizes, colors, and styles.

Take a picture, display and read text.

When the KNFBReader app first starts up, you will be in the Image Capture screen. with VoiceOver focus on the Take Picture button. With the screen of the phone facing up, place the iPhone with the camera down in the center of the document with the phone in the same orientation as the document,portrait orientation is recommended, and lift the device straight up approximately 8 to 10 inches (letter format documents) or 27 to 32 cm (A4 format documents).

Held in this position, the camera is on the under side of the phone in the far right hand corner away from you. (Check your camera periodically to make sure that the lens is clean and unobstructed). Be sure to hold the phone so no portion of a finger or your hand is close enough to the camera to block the view of the document. For a normal 8 and one half by 11 inch (letter format) or 21 by 29.7cm (A4 format) sheet, the camera will see the entire page at a distance of 8 to 10 inches (letter format) or 27 to 32 cm (A4 format).

To take a picture touch the left side of the screen, and VoiceOver should say: “take picture.” Then you can gently double tap anywhere on the left hand side of the screen and the camera will respond with the distinctive sound of the shutter.

For best results, to avoid jiggling the phone while the picture is taken, try using a split tap command where two fingers are planted firmly on the left-hand side of the screen and then lift one finger to snap the picture. Hold the iPhone steady until you hear the camera shutter sound.

The image is processed for text. If any is found, the text is displayed automatically and read aloud as the Text Navigation screen opens. To pause or resume reading, double tap with two fingers together. Use the VoiceOver rotater and standard gestures to navigate through the text or additionally by using the navigation controls located at the bottom of the screen.

To save the document, activate the Save Document button located just above the recognized text in the right hand corner of the screen. To return to Image Capture for taking another picture, activate the Back button or perform the VoiceOver scrub gesture.

Picture-taking tips.

Sharp pictures are essential for optimal performance. Hold the iPhone steady by using both hands and brace your elbows on the reading surface, while still keeping the device far enough from the document to capture all the text.

For best results, place the text you want to read on a flat surface in front of you. Flatten the document as much as possible. Keep the iPhone level over the page. Fill the screen with the view of the document you want to capture.

To confirm your camera position or learn the feel of a well lined up picture, use the Field of View Report option. You can activate the Field of View Report by double tapping or split tapping the right-hand side of the screen and holding the phone still to listen to the report; you can then adjust the position of the iPhone above the page and repeat the process as needed. The goal is to have the phone close to the document but still far enough away that all four edges of the document are seen by the camera.

Practice will help in the beginning. Use a familiar document printed in clear type on an 8 and one half by 11 inch (letter format) or 21 by 29.7cm (A4 format) white sheet of paper for your initial practice sessions. Place the document on a flat surface having a plain dark, not shiny background. After some practice with aiming and taking pictures you will begin to know how the KNFB Reader app responds. You will also be better prepared to analyze and correct conditions you can control when performance does not measure up. A little practice and persistence can greatly improve performance.

Getting help.

A User Guide is available to explain many more features of the App including use of all buttons and controls on the Image Capture and Text Navigation screens.

Details about the Reader’s multi language and document type options are also presented in the Guide. The Guide can be downloaded by following the documentation link at

Click Here To Visit The Page And Get The User Manual

or from within the App itself by navigating to the About tab located on the settings screen. If additional help is needed after consulting the User Guide, please send email help requests to


Contact: Sensotec nv, Vlamingveld 8, 8490 Jabbeke.

Updated on ... July 28, 2016