It has been reported that Twitter is testing a tool that lets users create a bunch of linked tweets known as 'tweetstorm.' Currently, these connected tweets are sent out one by one, however with the new feature users will find it easier to send a tweetstorm all in one go.
The latest version of the function was spotted by Android Police, and is available for certain iOS and Android users that are a part of Twitter's Experiments Program. According to Android Police, multiple tweets can be added to a single thread via a "+" icon in the tweet composer. However it is unclear whether the tweetstorm limits to a specific number of tweets, even though it does seem to have the 280-character limit.
Tweetstorms are growing it's popularity among users, and Twitter has made some tweaks so that long threads can be easily followed. However if this new feature goes official it would certainly change the way threads are being sent out, making it simpler for everyone.
Twitter has recently doubled their iconic 140-character limit. With the current popularity of tweetstorm, it is highly likely that the feature which is being tested would become official soon.