Yet another way to watch television has emerged.

More than two million viewers watched some of the Thursday night NFL football game on Twitter each of the last three weeks, and several million more used it to watch the first presidential debate.

For those who didn’t, here’s how it works: After opening the Twitter app and clicking Moments, you click “watch live” to join the live stream. If you position your phone horizontally, you’ll see a full screen image of the broadcast – really no different from watching any other video. But if you hold your phone vertically, the live feed is isolated to the top third of the screen; below is a Twitter feed of hashtags related to the event. (You can also watch it on a computer screen.) The live “Twittercast” is the latest development I’ve explored in 15 years of researching the changing business of U.S. television.

These two events illustrate different potential for Twitter-distributed video. Neither offered a “game-changing” experience – yet. But these two experiments, arriving in quick succession, reveal the future of live TV, which hasn’t been significantly affected by the arrival of services like Netflix and Amazon.

That’s clearly about to change.