Accessibility Horizontal Review of The Screen Orientation API

Hello,

As one of my recent Action Items within the APA WG (ACTION-2153
<https://www.w3.org/WAI/APA/track/actions/2153>) I was to do a horizontal
review of this emergent W3C Spec. These comments are based upon the current
Editor's Draft at https://w3c.github.io/screen-orientation/

While it is appreciated that this is primarily an API specification, APA
notes that there is a section in your draft labeled *5. Interactions with
other specifications*, and we would like to make you aware of a recent
addition to the WCAG 2.1 Specification, currently at Proposed
Recommendation with a (target) Recommendation Date of June 2018.

One new Success Requirement there states:

*Success Criterion 1.3.4 Orientation​ (Level AA)*

Content does not restrict its view and operation to a single display
orientation, such as portrait or landscape, unless a specific display
orientation is essential.

NOTE
Examples where a particular display orientation may be essential are a bank
check, a piano application, slides for a projector or television, or
virtual reality content where binary display orientation is not applicable.
​(source: ​
​https://www.w3.org/TR/WCAG21/#orientation)​


​
APA recognizes that this is primarily authoring advice, however given it's
criticality to some impacted users​ (primarily users with Mobility
impairments - ref: http://john.foliot.ca/orientation), we would appreciate
a pointer from your spec to this emergent Success Criteria as a proactive
advice to all content creators. To be clear, this is not "forbidding" the
use of screen lock, but it is a warning that end-users MUST be capable of
over-riding this author 'suggestion' to meet their specific needs (within
the range of exceptions noted in the SC).

*Proposal:* (offered as potential text only)

5.5 Interaction with WCAG 2.1

*This section is non-normative.*

The Web Content Accessibility Guidelines 2.1 specification [*W*CAG 2.1
<https://www.w3.org/TR/WCAG21>] includes a Success Criteria (SC 1.3.4
<https://www.w3.org/TR/WCAG21/#orientation>) related to screen orientation.
*​*The intent of this Success Criterion is to ensure that all content and
functionality is available regardless of the display orientation (portrait
or landscape). Some websites and applications automatically set the screen
to a particular display orientation and expect that users will respond by
rotating their device to match.

However, some users may have their devices mounted in a fixed orientation
(e.g. on the arm of a power wheelchair). Therefore, websites and
applications need to support both orientations by making sure content and
functionality is available in each orientation. While the order of content
and method of functionality may have differences the content and
functionality must always be available. When a particular orientation is
essential, the user needs to be advised of the orientation requirements.​
(source: https://www.w3.org/WAI/WCAG21/Understanding/orientation.html)


We would be happy to further expand or discuss this if you so desire.

On behalf of APA.
This now closes my Action item.

JF
​---
John Foliot
Principal Accessibility Strategist
Deque Systems Inc.
john.foliot@deque.com

Advancing the mission of digital accessibility and inclusion