Helping out the more visually impaired, Twitter is introducing image descriptions—also known as alternative text or alt text—into its Android and iOS apps. The social network wants their content to be as accessible to as wide an audience as possible. To enable the feature, head over to the accessibility settings of Twitter app and switch the slider to on for the “compose image descriptions” option. So, the next time you compose a tweet with an image, there’ll be an add description button. The descriptions can be up to 420 characters. For those who are visually impaired, you’ll see these descriptions via the assistive technology on your devices.
Source: Twitter