While fans were watching the Philadelphia Eagles beat the New England Patriots in Super Bowl LII, Verizon was quietly using the U.S. Bank stadium in Minneapolis, Minnesota for multiple live tests of its next-generation 5G wireless technology. The tests were notably conducted with Samsung 5G hardware on live 5G networks during very active use of 4G networks already in the stadium. And they spanned three cities: Minneapolis, New York City, and Seoul, South Korea.

A seemingly simple 5G demonstration of international video calling was actually packed with new technology. Verizon CEO Lowell McAdam and Korea Telecom (KT) CEO Chang-Gyu Hwang completed what the companies describe as “the first-ever 5G video call on prototype 5G tablets developed by Samsung,” making a call from Minneapolis to Seoul. According to Samsung, the 5G tablets can deliver “multi-gigabit per second speeds” on 5G, top 4G/LTE speeds, and proper switching between 5G and 4G networks.

The test was noteworthy due to its reliance on new end-to-end 5G hardware and two separate carriers’ 5G networks, all of which worked in the tests. Beyond the prototype tablets used by the CEOs, Samsung also supplied 28GHz 5G access units and home routers for the test, suggesting that it is closer to supplying consumer 5G hardware than was previously known. KT plans further 5G demonstrations at the PyeongChang Winter Olympics later this week.

Verizon’s more demanding demonstration used virtual reality headsets to show the incredibly high bandwidth and low latency 5G will offer. The carrier streamed live, 180-degree stereoscopic video from the Super Bowl field in Minneapolis directly to VR headsets in New York City, as well as offering “a virtual in-stadium experience, including high-resolution replays on secondary screens,” that apparently demanded multiple 4K and HD video streams over 5G.

5G networks promise to increase data speeds 10 to 100 times over today’s typical 4G/LTE connections, reduce latency to the 1-millisecond range, dramatically improve security, and radically expand the number of simultaneously connected devices. Many companies are beginning or continuing real-world tests of 5G technology in anticipation of 2019 or 2020 rollouts, but Verizon’s efforts are of particular interest as the company has promised to offer 5G this year, well ahead of most competitors.