Use Case Explorer
What can you actually do?
Pick a real-world use case and see exactly which generation makes it possible - and why the ones before it fall short.
SMS
Short text message delivery - plain, reliable, and usually the first thing that gets through when a network is struggling. The original killer app of mobile, older than mobile internet itself.
“You're stuck in a meeting and need to cancel plans without saying a word - you tap out a text under the table and it's done.”
Requires: ≤1000 ms latency, ≥1 Kbps down, ≥1 Kbps up, ≥95% reliability
SMS was invented for GSM. 160 characters over signalling channel - works perfectly.
SMS works on all 3G networks; over the circuit-switched domain.
SMS continues to work via SMS over SGs (relayed through the legacy core) or SMS over IMS.
SMS works over 5G via IP-based messaging.
Legacy messaging would depend on operator services and interworking; 6G support has not been specified.
Mobile Web
Loading an actual website - not a stripped-down WAP page - on a phone. Needs enough sustained throughput to pull down HTML, CSS, and JS without the page falling apart mid-load.
“You're at dinner, an argument breaks out about who directed a film, and someone pulls out their phone to settle it in three seconds flat.”
Requires: ≤500 ms latency, ≥500 Kbps down, ≥100 Kbps up, ≥95% reliability
WAP and GPRS enabled basic web access but pages were designed specifically for the constraints. Real websites were unusable.
Typical 3G speeds of a few Mbps made real mobile browsing viable. This was the generation that made the mobile web real.
30+ Mbps and 50ms latency makes mobile web indistinguishable from broadband for most browsing.
200+ Mbps and 10ms latency - faster than most home broadband.
The illustrative throughput estimate would support demanding web use, but 6G user performance is not yet known.
HD Streaming
Watching 1080p video from a service like YouTube or Netflix without it dropping to a blurry mess or stalling to rebuffer every few minutes.
“You're on a 90-minute commute and want to watch the episode everyone was talking about at work - without it stuttering every two minutes.”
Requires: ≤150 ms latency, ≥5.0 Mbps down, ≥500 Kbps up, ≥99% reliability
Max 384 Kbps vs 5 Mbps required. Even a compressed 360p stream was impossible reliably.
HSPA+ can deliver 5 Mbps but reliability and latency make buffering common. SD streaming was the norm.
4G's 30 Mbps realistic speeds easily support 1080p streaming.
Trivially supported. 5G's bandwidth headroom makes HD streaming a fraction of capacity.
HD streaming is already possible on current networks; 6G offers no established user-level advantage for this use case.
4K Streaming
The step up from HD: four times the pixels, and a network that has to sustain a much higher bitrate for the whole runtime, not just burst to it.
“You mirror your phone to the living room TV to show family your holiday videos - and you want them to look as sharp as the day you filmed them.”
Requires: ≤100 ms latency, ≥25 Mbps down, ≥1.0 Mbps up, ≥99% reliability
Two orders of magnitude below what 4K requires.
25 Mbps sustained is beyond reliable 3G throughput.
LTE-Advanced can support 4K, though consistency depends on network load.
4K requires 25 Mbps - well within 5G's realistic throughput even in congested areas.
The illustrative throughput estimate exceeds typical 4K streaming needs, but real 6G performance is not known.
Cloud Gaming
The game runs on a server somewhere else entirely - your device just streams the video and sends back your inputs. It only feels real if the round trip is fast enough that you never notice the join.
“You left your gaming PC at home but your friend just challenged you to a match - you open the game on your phone and expect it to feel like you never left your desk.”
Requires: ≤20 ms latency, ≥35 Mbps down, ≥5.0 Mbps up, ≥99.9% reliability
600ms latency vs 20ms required. Even ignoring bandwidth, this fails on latency alone.
120ms latency is 6x too high. Even mid-tier games require <20ms for a good experience.
50ms latency is technically above the 20ms threshold. Some cloud gaming works on 4G but input lag is noticeable in fast-paced games.
5G meets cloud gaming's 20ms and 35 Mbps requirements in deployed mmWave and sub-6 GHz networks.
Research targets could benefit cloud gaming, but latency and availability depend on the full network and service path.
Massive IoT
Millions of cheap, low-power sensors packed into a single square kilometre - parking bays, soil moisture probes, shipping containers - each sipping so little power it might run for years on one battery.
“A city council needs to monitor 40,000 parking bays, 12,000 streetlights, and 6,000 waste bins - all simultaneously, on batteries that last years.”
Requires: ≤1000 ms latency, ≥10 Kbps down, ≥10 Kbps up, ≥99% reliability, ≥100K / km²
GSM was designed for voice; device density per cell was measured in hundreds, not millions.
3G networks support thousands of devices per cell, not millions.
NB-IoT was added to LTE in Rel-13 as an overlay, but density and power efficiency fall short of 5G mMTC targets.
mMTC is a core 5G service family targeting 1 million devices/km². NB-IoT and LTE-M, which ITU-R accepted as meeting the IMT-2020 mMTC requirements, deliver years of battery life.
Some research explores higher device-density targets. The 6G target and how it compares with 5G remain subject to standardisation.
AR / VR
Overlaying or replacing your view of the world convincingly enough that your brain stops questioning it - which takes very low latency and a lot of bandwidth, since any delay shows up instantly as nausea-inducing lag between your head movement and the picture.
“An architect walks a client through a building that doesn't exist yet, overlaying full 3D plans onto an empty plot of land in real time - no headset jitter, no lag.”
Requires: ≤10 ms latency, ≥100 Mbps down, ≥50 Mbps up, ≥99.9% reliability
Requires >100 Mbps and <10ms. 2G provides 0.1 Mbps at 600ms.
AR/VR needs >100 Mbps and <10ms. 3G achieves neither.
100 Mbps sustained and 10ms latency both exceed reliable 4G capabilities - especially in congested areas.
5G enhanced mobile broadband (eMBB) delivers >100 Mbps, and with edge computing latency near 10ms - meeting AR/VR requirements in good coverage areas.
Future immersive applications are a research motivation; their requirements and achievable experience will depend on networks, devices, and application design.
Remote Robotics
Tightly synchronised control of machinery over a wireless link - robotic arms on a factory floor, automated guided vehicles in a warehouse - where a dropped packet or a few extra milliseconds of lag isn't an inconvenience, it's a safety incident. A 1ms round trip also limits distance: light in fibre covers only about 100 km and back in that time.
“On a factory floor, a controller a few hundred metres away keeps a team of robotic arms moving in lockstep around a production line - where a late command could mean a collision.”
Requires: ≤1.0 ms latency, ≥100 Mbps down, ≥100 Mbps up, ≥99.9999% reliability
No deployed generation fully meets these requirements yet.
A 1ms latency requirement is roughly 600x lower than 2G's typical latency.
Nowhere near the 1ms latency requirement.
1ms ultra-reliability is a fundamental architecture requirement, not achievable with LTE's EPC design.
URLLC targets 1ms but real-world deployments typically achieve 5–10ms end-to-end. Whether future 6G systems can close that gap is still a research question.
Low-latency, high-reliability communications are being studied for robotics. A research target alone does not establish safety or clinical suitability.