Though operating systems have come a long way in recent years, and technology has been introduced to enhance the user experience for the blind, immobile and visually-impaired, developers must still take responsibility to build software that works for everyone, regardless of their ability.

By making simple, straightforward changes to your Android and iOS apps, you’ll not only open your products to a wider audience but ensure nobody is left behind.

Below, we’ve rounded up some tips on building an accessible app.


Consider text to speech

Though it’s natural to want to create an all-bells, all-whistles app with graphics and video, be mindful of people who are visually impaired who may not be able to see your images, video, or GIF content. Don’t alienate those who are using text-to-speech voice technology; include video and graphics, but back them up with text to explain how your app and features work.


Stick to native controls

Rather than trying to reinvent the wheel with your app, stick to native controls that your users will be familiar with. For example, users should be able to swipe left to go back and right to go forward – follow guidelines and avoid overthinking the way users navigate your app.


Simple controls

As well as following developer guidelines, make sure your own user interface controls are easy to see and tap. Interactive elements, like buttons and form fields, should have a touch target size of at least 48dp ✕ 48dp, though the larger the better. But check that the target is accurate – you don’t want users to be tapping for the Name field but accidentally press Send!


No time-based content

We recommend avoiding time-based video and audio content that users may struggle to follow or keep up with – and if you do have to adopt this strategy, allow for content to be repeated. You should also add captions to all audiovisual content that sync at the right time.


Adjustable text

Though iOS and Android users can adjust the size of their text and in some cases, fonts, colours and brightness, your app should allow for greater personalisation within the settings menu. Add a slider that allows users to see the font and colours; remember that different users have different needs. Colour-blind users and visually impaired might prefer different fonts, colours, text sizes, and button sizes. Test all possible combinations for compatibility.


Colour contrasts

Something else to consider when developing an accessible mobile app is colour contrast – the difference in brightness between the colour of the text and the colour of the background. It is simple; you’d never choose a purple background and bright green text. Google’s Android recommends a contrast ratio of 4.5:1 for text smaller than 18pt, and 3:1 for other elements.



If you’re offering an app for iPhones and iPads, there should be clear continuity between the two to make the transition from one to another as straightforward as possible. The same can be said for rotation – your app should show the same content whether it’s in landscape mode or portrait, and users shouldn’t have to scroll or zoom to pick up from where they left off.


Think about colourblindness

Around 8% of men and 1% of women in the world are colourblind. Accommodate their needs by clearly separating the foreground and background on each screen and labelling elements with names and symbols rather than colours. For example, rather than instructing users to “press the blue button” to move forward, ask them to “press the button with the triangle on it”.


Think about assistive technology compatibility

The good news is that companies such as Google and Apple are increasingly working on accessibility features, most recently Apple with its VoiceOver feature which describes exactly what’s happening on an iPhone, iPad, Mac, Apple Watch or Apple TV. Think about the tech that is already in development and make sure your app is compatible with it. Native features on Android and iOS are beta tested for months before they’re launched to the public, so get in on the action and test new functionality so users can make use of it as soon as they get it.


User test

Though there are a clear set of guidelines to follow for making sure your app is accessible, the only way to know whether it works is to test it with real users. Of course, you could test yourself, but creating a focus group of disabled users who can point out things you need to improve upon makes sense. Ask for blunt feedback and implement changes where you can.


According to government data, there are more than 14 million disabled people living in the UK – that’s 22% of the population.

Though the changes we’ve offered above won’t make your app more accessible to all of them, the more tweaks you can make, the more people you will reach. Depend on the app development experts at Zudu if you’re looking to build an accessible app for your business – call us on 01382 690080 to schedule a free consultation.

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