Accessibility considerations for mobile design (Draft 9, Engage 0.3)
The following accessibility considerations are based on feedback received during QA testing with VO. References to WCAG guidelines are indicative as it is not clear to what extent they might apply to mobile applications.
Accessibility consideration |
Context in Engage 0.3b |
WCAG 2.0 |
---|---|---|
Perceivable |
|
|
For images used with special intent, the text description to be provided will be guided by their purpose. |
Thumbnail links to artifacts and exhibitions need to be provided with the link label. |
|
Size and contrast standards are to be met for input controls. |
Numbers on buttons need a contrast ratio of at least 4.5:1. |
|
Operable |
|
|
Input areas must be navigable with assistive technology. |
Code input area needs to be readable by VO. |
|
Users must be given an opportunity to adjust the timing or pause events like animations, transitions, or page redirects. |
Artifact page opens automatically upon entry of second code digit. |
|
Enough duration for timed messages is to be provided for assistive technology users to access them. |
Status and error messages in Code Entry screen need to be accessible. |
|
Title of web pages must describe their topic or purpose. |
Web page titles need to be the same as the application screen titles. |
|
Same navigation order is to be maintained with and without assistive technology. |
Currently, visual order in the Navigation bar is: |
|
Destination of image links is to be specified as part of the link label. |
Thumbnail links to exhibitions (currently have alt-text same as the title, which serves the purpose). |
|
Understandable |
|
|
Feedback about change of state within the same page must be accessible to assistive technology. |
When "Switch to grid layout" is invoked from list layout screen the change in layout needs to be fed to VO. |
|
Buttons indicating changed states must have descriptions verbose enough to differentiate them. |
"Uncollect" / "Collect" might be described as |
|
Status and error messages must be accessible to assistive technology. |
Status and error messages in Code Entry screen need to be accessible. |
|
Single tappable region with multiple objects must not be read by assistive technology as multiple different links to the same destination. |
Each of the three objects (1) thumbnail image, (2) text and (3) duration are read out as separate links to the same exhibition (making the 'duration' link confusing). |
|
Robust |
|
|
Critical steps must be designed such that they that do not depend on user agent behaviour. |
On page transition, VO on OS 3.0 announces page title whereas VO on 3.1.3 does not. Further, focus does not automatically fall on new page in either versions. New page should get announced and focus should fall on it irrespective of the version used. |