The new mode allows users to view more of the user interface at once, such as inbox and direct messages, a new compose window and threaded conversations. Much like other iPhone 6 Plus apps, the new UI looks similar to the app on the iPad.
“The most awesome stage”
Last year, Facebook's VP of Design thought the TNW Conference main stage was the best she'd ever been on.
At the moment, landscape mode is only available on the iPhone 6 Plus. If you haven’t seen the update yet, hang tight – Twitter likes to roll out changes in phases.