Posted on by Dean Holden in Design and development
TVs, set-top boxes and streaming devices are a huge part of all our lives and should be accessible so everyone can watch what they want, when they want, how they want.
We've started exploring challenges people with disabilities may face when interacting with TV apps and considerations for people designing and developing TV app interfaces.
How we experience TV depends on a mix of hardware and software working together to create the user experience. This includes set-top boxes, remote controls, platform accessibility settings, and support for assistive technologies such as screen readers and voice control. All of these will influence the accessibility of your content within a TV app.
If we then factor into this that TV platforms are built using different technologies and engines, designing TV applications can be very challenging. This post draws on best practice guidance from the Code of Federal Regulations - § 79.107 User interfaces provided by digital apparatus and other references to help you get started.
We document considerations around TV application accessibility from the perspective of different types of people using them and for people designing the interfaces. We touch on platform limitations and potential challenges TV app developers may experience as well as put forward possible workarounds and design considerations. It's not an exhaustive list and will have gaps we will continue to document as we explore more.
We reviewed the following platform accessibility guidelines and general accessibility guidelines to establish what the common challenges and themes might be.
Screen readers are software that enables people with limited or no vision to listen to on-screen content.
People who rely on a screen reader should be able to navigate around a TV app with a screen reader announcing everything that conveys meaning visually, including text and non-text, for example:
Some TV platforms like Panasonic and Samsung have built-in Voice guidance. While other TVs and streaming devices may use the Android operating system, which supports the TalkBack screen reader. Other platforms won't have any support or partial support.
Arguably people who need a screen reader will have a TV or streaming device with a screen reader, but with the latest technology having better support, it becomes a question of affordability. Upgrading either TVs or streaming devices to the latest versions can be expensive and not always possible.
Audio cues are a helpful way to reinforce meaning for people who are blind, have low vision, or are unaware of what is happening on screen. For example, a "beep" indicates an incorrect action or that you have reached the end of a screen or list.
Avoid using audio cues alone and combine them with visual cues as people who are Deaf or hard of hearing, in a noisy environment, or people who have audio cues switched off won't benefit from them.
A good approach is to use audio cues to reinforce meaning that has already been conveyed, such as a beep combined with an error message.
Remote controls can be hard to use for people with mobility and dexterity issues and people who can't see the small icons on buttons. Voice control is a valuable way to bypass having to use remote controls for journeys or searches that will require multiple button presses. Instead it can help people to comfortably find their desired content through, for example, a single button press and their voice.
Not all platforms support voice control, while other platforms have better speech recognition engines than others. As with all these features, support is better in the latest TVs and streaming devices, which brings us back to the issue of affordability. Some people with limited mobility who would benefit from voice control may also have limited speech, so can't access it.
Voice control shouldn't be relied on alone as people with limited or no speech won't be able to use it. Think of voice control as adding value to an app that supports interaction fully via the remote control.
Customising how you view content on screen helps improve the clarity of visual elements and supports personal preference.
This is helpful for everyone, especially those with low vision, cognition or learning disabilities. For example, people may want to increase text size, zoom into content, change colours, or use high contrast modes.
As with screen reader support and voice control, support for customisation depends on the platform. However, there may also be opportunities to support customisation for people within your app. For example, the iPlayer TV app has a feature where you can choose different font sizes for subtitles.
Images are vital in TV and streaming device apps as they help people recognise shows. For example, apps will use the thumbnail image of shows for people to navigate and select.
While this works for some, not everyone can recognise the images and some thumbnail designs might be too difficult for people with challenges with recall and memory.
Consider providing the image with the programme's name adjacent to it so that people can navigate by the visual or the text.
If the text is presented on an image, ensure it is still readable with large enough fonts and good contrast. Consider obscuring the underlying content when the image has focus so the text is more prominent.
Colour is a valuable way of conveying meaning and reinforcing understanding. For example, it can be used to colour code different programme categories (drama, comedy or lifestyle programmes) or channels such as BBC One, Two, and Three on BBC iPlayer.
We can't all recognise colour, so meaning should also be conveyed in other ways.
Consider using colour in combination with text and other visual cues to indicate an action, require a response, or identify an element. For example, use a border or underline for selected elements such as menu items.
Remember that good contrast is needed when conveying meaning so people can perceive the change. Read colour contrast below for more.
People need good contrast in order to read the content. This applies to text and non-text, such as icons and other non-decorative images and their background.
Defining good contrast on TV is not easy. The WCAG requirement of 4.5:1 for small text and 3:1 for large text and non-text can't be applied because TV is a vastly different environment to viewing web content on a desktop or mobile phone. TV is designed for viewing at a distance, so colours are saturated and more luminescent. As with contrast on mobile, the environment and lighting may also change depending on the room a person is in and the time of day. Different displays and settings may also affect contrast.
Flashing elements and movement can be a distraction, making content uncomfortable and difficult to read. For some people, it can trigger seizures, headaches, or nausea.
Minimise movement where possible. For example, if an error notification appears to indicate that there has been a loss of internet access, you could use a micro-animation to draw people's attention to it, but it should not keep flashing.
To some extent, everyone is a keyboard user when interacting with TV apps, as most of us use remote control to move focus around the screen.
People should be able to visually track where the focus is on the screen and identify selected menu items, form inputs, buttons and controls.
Design borders or underlines around the focused element. If the element already has a border, avoid relying on a colour change alone and provide good contrast. For example, if the element is placed against a black or otherwise dark background, the focus indicator could be yellow (or equivalent) to provide good contrast. If the element is placed against a white or otherwise light background, the focus indicator could be dark blue (or equivalent).
Using a remote control may not be possible for everyone. Remotes can be hard to hold and lift for people with limited dexterity, for example. Many platforms support navigation using an external Bluetooth keyboard, such as Apple TV, Fire TV, and Android TV, which are more comfortable for some people to use.
As with screen readers and other accessibility settings, support for external keyboards will vary. The question of affordability and having the latest TV or streaming device that supports Bluetooth is also a factor.
As a general good practice, design interfaces that minimise the number of steps needed to complete tasks and therefore reduce the key presses needed to get to desired content. For example, consider adding a filter on a search results screen so people can remove unwanted content and avoid unnecessary presses.
Keyboard navigation should also be logical and sequential. Remote controls do better at spatial navigation using the up / down, left / right arrow buttons, and other shortcut buttons such as Play, Pause, Back, Menu, Close etc. than a keyboard where these options are not always available.
People need obvious and easy ways to get to alternative formats such as captions, audio descriptions (AD), and signed versions of content (where they are supported).
Many remote controls have buttons to switch AD and captions on and off. However, this shouldn't be relied upon as not everyone will have a remote with that capability. Additionally, some people may not know their remote has that capability or be able to see the buttons to use them.
Consider providing multiple ways for people to find alternative formats within the UI:
Another consideration is some people may always want alternative formats, while others may want them occasionally. For example, someone who is Deaf may always want captions switched on and will do so via their settings or remote. Someone who occasionally uses captions will want access to captions within the player controls.
Consistent design helps people familiarise themselves with an app and how to use it. This could be the consistency of layouts and positioning of functionally over repeated pages and consistent styles for buttons and controls.
Consistency can be thought about in three ways.
Firstly, consistency with general design patterns from TV or media player landscapes. For example, using familiar icons for player controls: play, pause, volume, rewind, forward wind etc.
Secondly, consistency with platform design patterns. By using familiar patterns, people will better understand how to navigate the UI. For example, Apple's Planning your tvOS states:
Assemble your UI from standard views: Build your UI from buttons, text labels, and other standard views and controls in tvOS when your content doesn't change significantly between releases. Customise the appearance of controls, or create entirely new views to present your content in unique ways. Your UI remains local to Apple TV, and you fill it with data you obtain locally or from the network.
People are already familiar with using standard views and controls, which helps enormously. You can then customise the controls for a unique experience.
Thirdly, consistency with design patterns within your app. This means using consistent language and labels for controls, positioning repeated controls in the same across screens etc. Some thought could also be given to repeating design patterns from experiences on other platforms, such as mobile and the web. For example, like many TV apps, Netflix has an Audio and Subtitles menu that can be accessed via the player controls within the TV app, mobile apps, and on the web. Each has the same functionality, headings, look and feel.
We all need variable times to read content or complete actions. If content or tasks are time-based, ensure people are given adequate time to do what they need.
For example, if a programme summary appears on focus, give people sufficient time to read it before it disappears, or better yet, make sure it does not automatically disappear after a set amount of time. Give people control over content by providing a close button.
People need easy an obvious ways to find help and support.
Provide support services at no extra cost and accommodate various communication needs for people with disabilities. Possible support services include, but are not limited to:
Depending on the nature of the issue, some help or support features might be mapped to the TV platform. Minimally a link to a help page should be provided.
Find out more about how our design review and assessments services can help you create more inclusive user experiences for people with disabilities watching TV.
With thanks to Graeme Coleman and Henny Swan for their contributions to this post.
Updated 14 August 2023.
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