DAISY Reading Apps User Requirements
Working Draft
13 April 2025
Editors:
Document History
Copyright © 2025 DAISY Consortium
Working Draft
13 April 2025
Editors:
Document History
Copyright © 2025 DAISY Consortium
This document is the main output of the DAISY project to develop user requirements for reading apps. The project draws on the collective expertise and experiences of DAISY Consortium members and friends to express user requirements of individuals with diverse print disabilities for reading digital publications.
This unique document is intended to inform developers and purchasers of specialized reading systems and provide inspiration for mainstream reading solutions.
The user stories referenced in this document were developed by the working group.
User story: Oxana, Ruth, Alex, Stefan, Javier
The user should be able to change the typeface of all text, choosing from a range including sans serif and serif fonts. Individuals with low vision or dyslexia often have specific preferences for font styles that optimize their reading experience. Typefaces with preferred letter shapes can aid in visual processing, improve comprehension and reduce cognitive load.
Priority: Must-have
Sources: visual-010 : Change font, Accessibility Requirements for People with Low Vision: font face
Visual readability of text requires good visual contrast. Visual contrast is a product of the text characteristics, such as font weight (thickness, font stroke width) and font size, the lightness/darkness difference of the colors used for the text and the background, and other factors. For some people, bold text is easier to read which is why they should be have bold font options. Many typefaces have a bold font and some offer variable weight.
Priority: Must-have
Sources: WCAG Accessibility Guidelines 3.0 - Draft version: visual contrast of text, Accessibility Requirements for People with Low Vision: text style
Some people need to increase the size of text in order to read it. Although increasing size is most common, some people with tunnel vision and good visual acuity may prefer to decrease the size so they can see more text at a time.
Priority: Must-have
Sources: visual-010 : Change font size, Accessibility Requirements for People with Low Vision: font size, The effect of print size on reading speed in dyslexia. Journal of Research in Reading
For some people, it is difficult to read text that is italicized, underlined or bold. Users should have the option to view the text without these visual formatting styles. However, underlining should be retained for hyperlinks. While removing formatting may result in the loss of some semantic significance, users should be able to toggle back to the visually formatted version as needed.
Priority: Should-have
Sources: Accessibility Requirements for People with Low Vision: text style
Text written in all capital letters or all small capital letters is more difficult to read for most people, with and without disabilities. Users should have the option to choose a sentence-style version. Acronyms that are correctly marked as abbreviations will remain in uppercase; otherwise, they will be converted to sentence style. Users should also be able to toggle between the different styles as needed.
Priority: Could-have
Sources: Accessibility Requirements for People with Low Vision: capitalization
The amount of line spacing (leading), word spacing (space between words) and letter spacing (space between letters/characters) impacts readability. Some people need more space to read text and will have individual preferences. Line spacing also helps with tracking.
Priority: Must-have
Sources: Accessibility Requirements for People with Low Vision: line spacing, Extra-large letter spacing improves reading in dyslexia.
Justification impacts readability and tracking. Fully justified text creates uneven spaces between words and letters, leading to “rivers of white space” that disrupt reading flow and visual tracking, particularly for people with dyslexia. Users with low vision who rely on screen magnifiers may encounter exaggerated gaps or overlapping characters in justified text, making it harder to read. Center-aligned text is also problematic for multi-line blocks, as it disrupts smooth reading flow and makes it harder to find the beginning of lines. Depending on the reading order of the language concerned (left to right, or right to left) turning the justification or center-alignment off results in a left-aligned or right-aligned text.
Priority: Must-have
Sources: Accessibility Requirements for People with Low Vision: justification/alignment
Having wide margins results in shorter line lengths. This can be helpful for some people with specific learning disabilities. Having wide margins around blocks of text helps some people focus on the text and not get distracted by other content.
Conversely, wide margins can make line length too short for people who use large text.
User story: Oxana
Priority: Must-have
Sources: Accessibility Requirements for People with Low Vision: margins and borders, Shorter Lines Facilitate Reading in Those Who Struggle
For reflowable content, if the reader offers a paginated view, then the user should also be able to vie it in a scrollabe view.
User story:
Priority: Must-have
Sources:
User story: Ruth
Priority: Could-have
Sources:
There are many ways this can be done. Here are some implementation examples: […]
User story: Alex
Priority: Should-have
Source: ReadAloud-610 : Text is emphasised as it is spoken by read aloud
The user should be able to select an image and make it larger. There should be controls to adjust the size and to pan around an image when it no longer fits within the display.
A custom color theme used for viewing the text can sometimes render parts of the image difficult to see. There could be the option in the image viewer to revert to the default color mode, or to choose different color themes.
User story:
Priority: [Must-have]
Source: visual-710 : Enlarge SVG Images
Math expressions included as MathML (or LaTeX, if supported) should be displayed correctly. As the user adjusts the size and colors of the text content, the math expressions should change accordingly. As the text size is increased, so should the math expressions in proportion. As the user changes the colors for the text content, this should also affect the math expressions.
User story:
Priority: Must-have
Source: visual-550 : Viewing MathML
Math expressions often contain small symbols such as exponents, indices, dot notations and derivatives. It should be possible for the user to view a math expression as a separate item and enlarge it.
Priority: Should-have
Source:
Certain parts of math expressions are sometimes presented in special colors, e.g. superscript in red. For some people this can present problems. The user could be able to remove the color formatting used in math expressions so the chosen text color is always used.
User story:
Priority: Could-have
Source:
The user should be able to set the background and text color from the full color spectrum.
Some people need high contrast between text and background, including many older people who lose contrast sensitivity from ageing. Some read better with dark text on light background. Others find it easier to read with low contrast and colors that present less glare.
For some people, common color combinations or colors from a limited color palette work fine, for example, black text on white background or the inverse with white text on black background. For instance, black text on a white background is specifically useful for people with dyslexia. Other people need to select more specific background and text colors. For example, people who need low brightness overall, need to select the specific background and text colors that provide sufficient contrast for them yet not too high brightness. Readable and optimal color combinations differs vastly among individuals and can even vary for one individual depending on conditions such as fatigue and lighting.
User story:
Priority: [Must-have for a limited color palette; Should-have for more specific background and text colors]
Sources: visual-110 : Change background and foreground color, Accessibility Requirements for People with Low Vision: text contrast
Some people use high contrast modes on their device because it increases readability by maximizing the difference between text and background. Some people use the magnification feature of the operating system, or third party tools, to increase the size of text and images on the display.
Users must be able to use these features with the reading app. The app should respect the high contrast settings chosen by the user.
User story: Stefan
Priority: Must-have
Source: visual-310 : Apply high contrast system configuration
Some individuals with low vision or dyslexia may have photophobia or light sensitivity. The ability to dim the screen can make reading more comfortable for these users. For some people with age-related macular degeneration, brighter illumination has been shown to improve reading acuity, critical print size, and maximum reading speed. Adjusting brightness can enhance the contrast between text and background, making it easier for individuals with low vision to distinguish letters and words.
The user must be able to adjust the display brightness when using the reading app. If this is not possible on the device or the operating system, it must be possible in the reading app itself.
If it is possible to adjust the display brightness on the device or in the operating system, it could be possible in the reading app itself.
Priority: Must-have
visual-210 : Change brightness, Legge G. E. (2016). Reading Digital with Low Vision. Visible language, 50(2), 102–125. (https://pmc.ncbi.nlm.nih.gov/articles/PMC5726769/)
Priority: Must-have
Source: EPUBTest file-210 Open content
For content with text it must be possible to move forward and backward from the currently displayed screen.
For content with audio it must be possible to move forward and backward using time-based navigation.
Priority: Must-have
Sources: EPUBTest nav-210 Navigate forward and backward through reflowed content, EPUBTest nav-510 Move across chapters without using TOC, EPUBTest reading-1210 : Navigate the content by headings, EPUBTest nav-110 Navigate content by pages
The focus must be on the entry for the current reading position when the user is presented with the table of contents. If the publication’s table of content comprises a hierachy of entries (eg volumes, chapters, subsections) then it must be presented as a tree view, nested list view or any other view that conveys the structure to the user. The user must have a mechanism to move between items in the table of contents of the same level (eg between the chapters without having to go via the subsections).
Page numbers or percentage information could be provided in the table of contents. The user could be able to search within the table of contents.
Priority: Must-have
Sources: EPUBTest nav-010 Navigate to chapters through the Table of Contents, EPUBTest nav-005 The table of contents in the app presents the content hierarchy
When the publication includes page markup then it must be possible to navigate by page numbers. If the publication does not include page markup it could be possible to navigate by ‘pseudo pages’ (where the app uses an algorithm to approximate navigation points equivalent to typical page lengths).
Priority: Must-have
Sources: EPUBTest nav-010 Navigate to chapters through the Table of Contents, EPUBTest nav-005 The table of contents in the app presents the content hierarchy
When reading audio-based content it must be possible to go to a specific location. This could be based on time, percentage, or another approach.
Priority: Must-have
User story: Maria
Priority: Must-have
Sources: EPUBTest reading-810 : Move to the next block item, EPUBTest reading-1110 : Navigate by lines, EPUBTest reading-1010 : Navigate by words, EPUBTest reading-910 : Navigate by characters
Priority: Must
Sources: reading-010 : Initiate “read from here”, “reading-110 : Stop and resume reading at the same reading location”
When reading text-based content it must be possible to return to the approximate location (such as the same page or screen of text). It could be possible to return to the exact last location.
When reading audio-based content it must be possible to return to the exact last location.
Priority: Must-have
The user must be able to get information about their current position in the book without losing their reading position. The minimum information expected is the percentage progress.
The user should be able to determine the current chapter, section, current page number where this information is provided in the publication.
Priority: Must-have
Source: nav-310 Read navigation information
In this requirements document the term “read aloud” refers to the app using Text To Speech (TTS) to provide an audio option for text-based content.
The user must be able to use a TTS read aloud feature for text-based content. If the publication also has synchronised audio with the text then the user must be able to choose the alternative of listening to the TTS read aloud.
Priority: Must-have
Source: ReadAloud-010 : The content can be read aloud
The user should be able to choose the position from where the read aloud begins. If the read aloud starts from the approximate reading position (eg on teh current page or screen) then the user must be able to easily move the read aloud position so that reading is happening from the desired location.
Priority: Must-have
The user should be able to select from a range of voices. The user must be able to choose the speed of the read aloud voice.
Source: ReadAloud-400 : Change Read Aloud reading voice
The read aloud must read continuously until the end of the publication unless interupted by the user.
Priority: Must-have
Source: reading-210 : All text should be read in the proper order, ReadAloud-310 : All text should be read in the proper order
Priority: Must-have
Source: EPUBTest reading-510 : TTS allows pause for indicating headings, paragraphs, list items, etc, ReadAloud-510 : Text to Speech handles punctuation and document structure appropriately
The text being read must be shown on the display as the read aloud position continues beyond the text initially visible.
The user must be able to visually emphasize the text as it is read aloud using a contrasting highlight, underlining, or other means.
The user should be able to change the color or style of the visual emphasis.
The user should be able to to turn off the read aloud visual emphasis.
Source: ReadAloud-610 : Text is emphasised as it is spoken by read aloud
Priority: Must-have
Source: reading-1510 : TTS Change Languages Automatically
User Story: Louis
The read aloud feature must be able to announce the alt text of images.
The user should able to turn off the read aloud of image alt text.
The image alt text could be distinguished from text content with an announcement, use of different voice, or other technique.
Priority: Must-have
The read aloud feature must be able to announce encoded math content (eg MathML).
The user should be able to adjust the announcement of math content according to their preference (eg relative reading speed, verbosity).
Priority: Must-have
Priority: Must-have
Source: nav-410 : Perform a search, review the search results
Priority: Must-have
Source: reading-210 : All text should be read in the proper order, ReadAloud-310 : All text should be read in the proper order
Priority: Must-have
Source: EPUBTest reading-510 : TTS allows pause for indicating headings, paragraphs, list items, etc, ReadAloud-510 : Text to Speech handles punctuation and document structure appropriately
Priority: Must-have
Sources: ReadAloud-400 : Change Read Aloud reading voice, ReadAloud-410 : Change Read Aloud reading speed
Priority: Must-have
Source: reading-1510 : TTS Change Languages Automatically
User Story: Louis
Priority: Must-have
User Story: Simona
Source: reading-310 : Image alternate text reading
Priority: Must-have
Source: ReadAloud-350 : Image alternate text reading
Priority: Must-have
Source: reading-610 : Navigate between the cells, rows and columns in the table
Priority: Must-have
Source: reading-710 : Navigate between internal hyperlinks
Priority: Must-have
Source: reading-420 : Footnote Reading
[Notes for editors: - The user should be able to explore mathematical expressions that are included as MathML or LaTeX. This is not expected if math is included as images.]
Priority: Must-have
User Story: Louis
Source: EPUBTest reading-1410 : MathML Reading
Sources: EPUBTest anno-010 : Add a Bookmark or Highlight, EPUBTest anno-110 : Review and navigate Bookmarks or Highlights
Sources: EPUBTest anno-210 : Add a note, EPUBTest anno-310 : Review and navigate Notes
This project would not have been possible without the contributions of the DAISY members and Friends who participated in the project. Their valuable insights, expertise, and experiences have been instrumental in ensuring that the requirments capture a broad range of user needs.
This work is financially supported by Dedicon.
The EPUB test: Latest test books has many well-established fundamental accessibility tests which were extracted and adapted for this document. The titles are: