AppleGoogle, and Facebook aren't the only ones who can play messenger.

AllThingsD is reporting that Twitter is preparing to overhaul its private direct messaging service. Twitter has long focused heavily on users being able to publicly broadcast tweets for all to see, although it has always had a direct messaging component as well. Messaging has become an important competitive field for tech companies, including the aforementioned heavyweights. On top of that, smaller companies like WhatsApp, which now has more than 300 million monthly active users, are also making a dent in the market.

Twitter inevitably won't be able to charge directly for any type of service, so it will instead hope such an offering would boost sales indirectly by reinforcing the core advertising business. This would be an engagement move, pure and simple.

In this segment of Tech Teardown, Erin Kennedy discusses Twitter's possible messaging service with Jamal Carnette and Evan Niu, CFA.