The iPhone 7 expected to debut on Sept. 7 may offer a glimpse into the future of smartphones, but it won’t have 5G. And even though the next generation of cellular is due to launch in 2020, high-end handsets may be LTE-only for years to come.

The advancement they’re counting on the most — and the hardest to achieve — is ultra-low latency, or very short delays between when a bit is sent and when a device receives it, IHS said. That’s important for things like robots, self-driving cars, and cellular-driven virtual reality. The goal is to reach 1 millisecond, quicker than LTE can achieve.