How Does Waze Work without a Cellular Connection?

by Barrett

We all know that navigation apps on your smartphone need to be online to function in your car. Or do they? Even with no bars, Waze can still get you where you’re going. Here’s how…

Yes, I must report that I’m still using my portable Garmin GPS in my Toyota RAV4. It’s admittedly difficult to defend my ongoing allegiance to this expensive older tech. My Garmin simply can’t compete with the more flexible user experience of navigation apps on smartphones.

But the good news is I’ve recently taken a big step forward… These days, I’ve been using Waze on my iPhone. All of the real-time traffic and hazard updates provide a nifty virtual view a few miles up the road. That’s hard to beat.

My Garmin Vs. My Waze
I shouldn’t admit this, but I often have both my Garmin and Waze operating simultaneously to see if they agree on the fastest way to go. And more often than not… they don’t. But that’s another story…

One advantage that I thought my Garmin Drive 50LMT still had over smartphone apps was its almost bullet-proof ability to maintain its GPS connection vs my iPhone’s uncertain cellular data tether while driving through dead zones. Navigation apps can’t survive that kind of hiccup, right?

But on a recent vacation road trip, I experienced what seemed to be impossible…
Waze was working without a cellular connection!

Offline iPhone GPS
My family and I were driving through some backroads in New Hampshire, and I looked at my iPhone, which was mounted to my dash via my Bunker Ring. I realized that while Waze had indeed lost all cellular connectivity, it still appeared to be functioning normally. As we drove, it continued to correctly display our location and the distance to our next turn. But it had no signal!

How was that possible?!

The Little-Known GPS Chip
After doing a little research after we got home, I realized that my iPhone was able to pull off this trick by using its built-in GPS radio. Yes, my iPhone has its own GPS functionality as do other smartphones! Its GPS chip operates independently of cellular data, and that’s why Waze was still able to see in the digital dark.

Sure, my Waze app was hobbled without its connection through AT&T. It couldn’t provide crowd-sourced traffic and hazard updates or recalculate my route. But Waze wasn’t entirely down for the count either.

I imagine at some point, Waze would have needed to connect back to its servers to download more map data, but for the fifteen minutes or so that I was driving offline, Waze was able to keep up with the twisty road ahead!

Impressive… most impressive.

Your Smartphone is at Home with GPS
There are actually lots of folks out there taking advantage of their smartphone’s GPS chip in places where cell coverage is nonexistent. They’re using apps designed to download maps ahead of time, before the trip begins.
(Waze can’t do this.)

But for me, I’m just exceptionally pleased knowing that Waze can survive for a while in a data-free zone using my iPhone’s GPS radio.

And if that can’t reverse my irrational allegiance to my Garmin Drive, I’m not sure what else will!