Instagram notes on its new website promoting IGTV that mobile video content will make up for nearly 80% of all mobile data traffic within three years.
Mr Systrom also announced a new feature enabling some users to share long-form videos up to one-hour long.
The app is aimed at what Instagram calls "creators", but anyone can create and upload their own videos.
In a press Q&A after the event, Systrom said there would not be ads on the videos for now but there most likely would be in the future. "IGTV is focused on the creators you love most and already follow on Instagram".
Creators can link to their Instagram profiles, outside websites or online stores in clips uploaded to IGTV. Systrom said Wednesday that Instagram now has 1 billion monthly users, and the Pew Research Center recently reported that 72% of U.S. teenagers say they use Instagram. "I'm still going to be posting on YouTube as well as on Instagram", she told reporters.
It's been said that Instagram wants to attract "web celebrities" to IGTV, rather than traditional media companies or publishing firms. As with Snapchat's Discover hub, IGTV videos will be vertical and will be separated across multiple channels, which can be browsed individually or happened upon via a smattering of content discovery tools. IGTV content will also be available in the Instagram app. IGTV videos will be able to go beyond the 60-second limit placed on videos uploaded on Instagram today.
IGTV is essentially a video platform, similar to YouTube, where each creator has their own channel which users can choose to follow to stay updated on. Instead, each video can be up to an hour long. IGTV could also spell more trouble for Snapchat which has been trying to make vertical video the most popular format among Millennials and teens.
Videos uploaded to IGTV will be vertically-orientated, so they can be viewed fullscreen on a smartphone when it is held in portrait.
Instagram is launching its long-form video platform today.
For creators and publishers, Watch is pitched as a platform to help them build an audience of fans and make money through advertisements - much like YouTube.
In September, Instagram said it had some 800 million monthly active users.