Tag up to 10 people in a photo
Tagging people in a picture makes conversations around photos fun and easy. And tagging doesn’t affect character count in the Tweet — you can tag up to 10 people in a photo and still have all 140 characters at your disposal, making it easier to connect with your friends. If you’re the one being tagged, you’ll get a notification. You can adjust notifications, as well as who can tag you, in your Settings.
Share up to 4 photos in a single Tweet
And now, you can also share a series of photos that automatically create a collage. Just tap on a preview to get the full image and slide through the group. The ability to upload multiple photos is starting to roll out today on iPhone, and is coming soon to Android and twitter.com.
Additionally, both photo-tagging and Tweets with multiple photos will display in Embedded Tweets.
You can download Twitter from the App Store for free.