How does the increasing preponderance of mobile device affect web accessibility? This talk focuses on the specific concerns that are raised when dealing with mobile devices. How does this affect decisions about responsive web design when we use a single codebase for different kinds of devices? What guidance do the recently released draft guidelines on WCAG 2.0 and the mobile web provide us?
Marco Maertens
2. 2
Mobile Accessibility?
• There is no mobile Web. Just one Web
• Is there mobile accessibility?
• Large overlap between mobile concerns
and accessibility
• Mobile has made us think not just about
mobile
3. 3
What Are Some Mobile Accessibility Differences?
• Touchscreen
• Screen size
• Easily adjustable orientation
• Use context
• AT implementation
4. 4
What is (W3C WAI) WCAG?
• An effort of the W3C
• Focused on Web accessibility
• Standards set by wide consultation
(world wide)
• The basis of many legal requirements
• Original and future basis of US
Section 508
5. 5
WCAG 2.0 Mobile Accessibility Mapping document
• A draft. Did a mention it’s a draft?
• Not a change to WCAG 2.0.
• Applies to mobile devices
• Targeted to web sites and web apps.
Hybrid and native apps can benefit, too!
6. 6
Perceivable
• Minimizing content
• Sufficient size (targets, fonts) to avoid
unnecessary zoom
• Zoom/magnification may be necessary
• Consider user may need to pan
• Contrast – even more important because of
context
11. 11
Understandable
• Screen orientation
• Consistent layout
• But differences in orientation or
size OK (important)
• Provide clear indication that element is
actionable
15. 15
Appendix A: The Four Principles of WCAG 2.0
Perceivable - Information and user interface components must be
presentable to users in ways they can perceive.
This means that users must be able to perceive the information being
presented (it can't be invisible to all of their senses)
Operable - User interface components and navigation must be operable.
This means that users must be able to operate the interface (the interface
cannot require interaction that a user cannot perform)
Understandable - Information and the operation of user interface must be
understandable.
This means that users must be able to understand the information as well as
the operation of the user interface (the content or operation cannot be
beyond their understanding)
Robust - Content must be robust enough that it can be interpreted reliably
by a wide variety of user agents, including assistive technologies.
This means that users must be able to access the content as technologies
advance (as technologies and user agents evolve, the content should
remain accessible)
Notas do Editor
There is no mobile Web. Just one Web
Is there mobile accessibility?
Mobile devices do present new considerations
When do we need to think about these considerations?
Think of tablets
Think of what else we don’t know about yet
Large overlap between mobile concerns and accessibility
Mobile has made us think not just about mobile
Touchscreen
Lack of cursor
Target size
Screen size
Easily adjustable orientation
Use context (but…)
AT implementation (VoiceOver/TalkBack)
http://www.w3.org/TR/mobile-accessibility-mapping/
A draft. Did a mention it’s a draft?
Not a change to WCAG 2.0.
Applies to mobile devices
Handhelds
Tablets
But also wearables (glasses, watches, fitness tracking devices), car displays, airplane seatback sets, refrigerator screens, etc.
Targeted to web sites and web apps. Hybrid and native apps can benefit, too!
Minimizing content [vision, motor control, cognitive]
e.g. Hidden menus, smaller images
Sufficient size (targets, fonts) to avoid unnecessary zoom [vision]
Font sizes are perceived smaller on a phone
Zoom/magnification may be necessary [vision]
Make sure to allow pinch-to-zoom with a correct viewport metatag
<meta name="viewport" content="width=device-width, initial-scale=1.0">
Consider user may need to pan [vision, motor control, cognitive]
Contrast – even more important because of context [vision]
Font size is perceived smaller on phones, so guidelines, should be more generous than the WCAG guidelines of 1.2em and 1.5em
Don’t forget keyboards, yes keyboards [vision, motor control, cognitive]
Touch-size minimum 9mm (but don’t specify physical units); even more important [vision, motor control]
Gestures – should be simple (conflict with expected system gestures) [vision, motor control, cognitive]
Mouseup/touchend reduces unintended interactions [vision, motor control, cognitive]
Orientation/shake/etc. should have keyboard equivalents [vision, motor control, cognitive]
Screen orientation [vision, motor control, cognitive]
Support changes when possible
Consistent layout [cognitive]
But differences in orientation or size OK (important)
Provide clear indication that element is actionable [vision, motor control, cognitive]
No indication from hover state or cursor change
Data-type keyboards: a double-edged sword [vision, motor control, cognitive]
Use standard elements and controls so built-in accessibility will work with it. [vision, hearing, motor control, cognitive]