The Highlights is update to tweets in reverse chronological order, and based on your previous behaviors (reply, Retweet, or like), present the feeds you’re most likely to care about at the top of your feed.
While the Highlights feature presents conversations and popular tweets within your network as well as topics and events that are trending in your location, it learns more as a user interact with the tweets, meaning the more you use it, the more accurate the suggestions get over time.
The rolling out of the Highlights feature requires users on Apple's iOS devices to opt-in to the feature, which Twitter will notify you through push notification twice a day to let you know your Highlights summary is ready.
And to enable Twitter Highlights on iOS, simply tap on the gear icon, go to settings, tap notifications and then mobile notifications.
