Twitter’s 140 character limit isn’t going anywhere intimated Twitter CEO Jack Dorsey in an ironically screenshotted tweet recently, but that doesn’t mean Twitter isn’t trying to let you cram as much info into those short micro-blogs as possible.

Twitter has today launched descriptions for images on mobile, letting you annotate the picture to describe it. :

Starting today, people using our iOS and Android apps can add descriptions — also known as alternative text (alt text) — to images in Tweets. With this update, we’re empowering everyone to ensure content shared on Twitter is accessible to the widest possible audience.

Descriptions can be up to 420 characters in length, allowing for a LOT of extra background on what the image, is, where it was taken and what made you want to share it.

To annotate a picture you’ll need to turn the function on in the Twitter app’s accessibility settings. Once switched on, next time you add an image you’ll get a thumbnail inviting you to add a description. Simply tap the option and you can type away till you have a great description to share.

The update is available in your Twitter for Android mobile app now, with Twitter extending the function to the REST API and Twitter cards as well.

Source: Twitter.