When you tweet an image, Twitter offers you the ability to add a description to that image. The description works via VoiceOver or other screen-reader technology to let anyone with low or no vision understand what's in the image even if they can't see it well or at all.

It's terrific for accessibility. All you have to do is turn it on and type it out.

Note: Image descriptions only work for images. Animated GIFs are treated like videos so you can't currently add descriptions to them.

How to turn on image descriptions for Twitter

Sadly, image descriptions aren't enabled by default on Twitter. You have to turn them on first. You can do it either on the web or in the app. Both are similar. Here's how it works in the app:

  1. Launch Twitter.
  2. Swipe to expose the sidebar.
  3. Tap on Settings and Privacy.
  4. Tap on Accessibility.
  5. Switch on Compose Image Descriptions.

    Screenshots of the Twitter interface for enabling image descriptions.

Once you've enabled them, adding image descriptions is easy.

How to add image descriptions in Twitter

You can add image descriptions for any and all pictures you post to Twitter. It's especially useful — and important — for images that don't benefit from any context or clarity already in the tweet itself.

  1. Tap the Compose button to start a new Tweet.
  2. Tap the Image button to pick an image.
  3. Tap Add a description at the bottom left of the image.
  4. Type in your description.
  5. Tap Apply.

    Screenshots of the Twitter interface for adding descriptions to images in tweets.

Whatever description you add will be what any low or no vision users will hear via VoiceOver or other screen reader technology.

Accessibility for everyone

Adding descriptions to images might seem like a hassle but it's an important way to make your images accessible to everyone. Even if you don't have low or no vision yourself, it'll benefit your followers, their followers, and — since we all get older and sometimes suffer occasional injury — ourselves as well.