Twitter mulling paid service called Twitter Blue, finds researcher

Monthly $2.99 subscription includes ability to organise tweets into collections and undo tweet' button

Twitter is considering launching a paid subscription service called Twitter Blue, according to unreleased features of the app discovered by an independent researcher.

Jane Manchun Wong, who has made a name for herself through uncovering accidentally-public upcoming features of popular apps, shared screenshots of the service, which is pegged at $2.99 a month.