Mobile platforms provide built in screen-reader technology that can be enabled on a users mobile device. The functionality can be accessed using specific gestures and interactions with the touch screen. The Palace App is built so that the on screen elements (buttons, controls, labels, text and icons and book cover jackets) can be read back to the user. The same goes for the eBooks its presents.
For Apple, the feature is called VoiceOver and for Android it is TalkBack
The touch screen interaction between iOS and Android are fairly similar but specific to each device and version of OS.
Users and librarians can reference the following to learn what gestures their device and OS version supports.
iPhone Users Guide to Voice Over
Google guides to Android TalkBack
<aside> 💡 Content limitations Some content however, that is purchased and distributed by various eBook providers were published prior to when web accessibility standards or EPUB 3.2 provisions were established. Some content is scanned and no OCR is available. In those cases the device screen-reader technology has nothing to read back to the user.
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Web Content Accessibility Guidelines (WCAG) is an international digital accessibility standard. It is technology agnostic and can be applied to any digital technology from the web to PDFs to native apps. There are three levels A, AA, AAA. Most organizations meet level AA. (For example, this is the standard used by Library of Congress and various governments including USA Federal.) The standard organized by 4 principles each with a set of guidelines. Guidelines are defined by success criteria, which are concrete. WCAG 2.1 is the most current version.
This wiki page includes WCAG requirements and best practices that can be applied to the work on the Palace Web Client. For the most part, it covers relevant HTML patterns supporting accessible functionality. There are also some notes on visual design.
<aside> 💡 Note: This is not a comprehensive list of the WCAG 2.1, level AA accessibility requirements, but the guidelines on this page set a strong baseline accessibility.
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