- It's a bit late, but T-Mobile has added an L4S real-time application upgrade to their 5G network
- Analyst Daryl Schoolar said this benefit both mobile and FWA customers
- T-Mobile said that the upgrade could help enterprises with video training, remote collaboration, or field support and more
Say goodbye to choppy video calls — at least if you're a T-Mobile customer.
T-Mobile has introduced a L4S update to its network, which it has previously described as a "5G-Advanced" upgrade to its standalone 5G (5 G SA) network, which will improve real-time video performance for both fixed and mobile T-Mobile users.
L4S stands for “low latency, low loss, scalable throughput,” and unblocks networks by allowing faster movements of data packets for specific applications in real-time. "L4S consistently delivers low latency, minimal packet loss and real-time responsiveness — even under heavy traffic," T-Mobile CTO John Saw said in a recent blog.
T-Mobile's president of technology, Ulf Ewaldsson, told Fierce Network in October 2024 that the L4S upgrade would arrive before the end of that year. It's about half-a-year late but now the update is here.
"Unlike hardware upgrades, enabling L4S doesn’t require ripping and replacing infrastructure. It’s a software-side capability that we’re implementing across our nationwide network," a T-Mobile spokesperson told Fierce in an email. "This began in late Q2 2025 and continues into Q3, allowing for broad deployment across our entire nationwide 5G Advanced Network."
T-Mobile said that extended reality (XR), delivering video to smart glasses and other devices, will become a key enterprise use.
"In trials with Qualcomm and Ericsson, L4S enabled high frame-rate AR/VR experiences on slim smart glasses, dramatically reducing motion sickness and lag critical for enterprise training, remote collaboration, or field support," the spokesperson said.
We'll see how it takes for companies to actually adopt such XR-glasses.
T-Mobile also noted that L4S enables teledriving for Vay, where precision and safety rely on real-time responsiveness and a high-quality video feed. "These examples of enterprise-grade use cases are where L4S shines, especially when paired with network slicing," the spokesperson said.
On the consumer side, the spokesperson noted that video calling will be "smoother and more natural" with L4S. They also said that gaming would be a key use case. "NVIDIA GeForce NOW already supports L4S, and with T-Mobile’s 5G Advanced network, the result is ultra-responsive, lag-free mobile gameplay that feels like you’re on a console," the spokesperson added.
L4S as an FWA-helper
Recon Analytics told Fierce that the upgrade both T-Mobile's mobile customers and its fixed wireless access (FWA) users. "L4S will improve all real-time application performance for both T-Mobile’s fixed and mobile users. With consumers I think where they will see the most noticeable improvement is gaming, especially those on T-Mobile’s FWA network," Daryl Schoolar told Fierce.
Schoolar thinks this could increase help increase network traffic as "consumers and businesses who were previously frustrated with real time application performance now starting to use those applications more thanks to L4S."
Another standalone win
"The L4S capability is network-side and works automatically when supported by the applications or services they’re using – like FaceTime. Content providers handle mitigation and adaptation seamlessly in the background, so the end user gets an improved experience —no downloads, toggles, or settings are required," noted the T-Mobile Spokesperson.
T-Mobile has previously said that its move to 5G-Advanced and the L4S upgrade was possible because it has a standalone network. As we've seen recently, the other two major U.S. are now slowly making their move into standalone. No word yet on when AT&T and Verizon will cut their video jitters.