These descriptions are also called alternative text (alt text), and they will now accompany images in Tweets. Such an update would empower just about anyone and everyone to make content shared over Twitter as being accessible to just about everybody.
Enabling this feature is a snap – all that you need to do is to make use of the compose image descriptions option within the Twitter app’s accessibility settings. Each time you add an image to a Tweet, individual thumbnails in the composer will then carry an add description button. Upon tapping on that option, you can then include a description to the image. Visually impaired folks can then check out the description through assistive technology like screen readers and braille displays. These descriptions will be longer than the 140-character limit, being up to 420 characters. [Press Release]