Google Maps thinks you’re driving alone. Waze thinks so too, and so does every other navigation app on your phone. Each one looks at where your car is and what the traffic ahead of it is doing, then picks the fastest route for that one car. The other cars in your group are not part of the math at all.
I watched this go wrong on the way to a wedding in Vermont last October. Five cars left the same parking lot in Connecticut a few minutes apart, all headed for a barn venue outside Stowe. The three cars up front were on Google Maps and the two in back were on Waze, and nobody thought to mention it. Somewhere near Brattleboro, Waze saw a slowdown on I-91 and pulled the back two off the interstate onto a state road. The lead car, which was me, kept going north. Nobody noticed until my cousin called from 30 miles away asking which exit we’d taken.
Thirty miles. With nobody missing a turn.
Why the Car Behind You Gets a Different Route
Each phone makes its own routing call. It weighs current traffic, closures ahead, your toll setting and whatever it has picked up about how you like to drive, and none of that is shared with the phone in the next car. Two drivers can leave the same driveway seconds apart and still get different answers, because the traffic picture moved in those seconds.
Picture the lead car clearing an interchange just before it backs up. A few minutes later the car behind hits the jam and gets offered a detour. Now the group is on two roads, and neither driver knows it.
Toll settings split groups too. If one driver has Waze set to avoid tolls and the next one doesn’t, they part ways at the first spot where a toll road runs next to a free one. I’ve lost cars like this more than once, and the drivers had no idea anything was different until we compared screenshots at the rest stop.
Gas stops do it as well.
Pull off to fill up and your app plans the rest of the drive from the station, using traffic data that’s newer than what the rest of the group got when they passed that point. You can get back on a different highway than everyone else and not find out until somebody asks where you are. Stop for coffee and a bathroom and the gap gets wider while you’re inside.
The “Just Follow Me” Fallacy
The usual fix is that one person navigates and everyone else follows. I ran trips that way for years. It works fine on a quiet road with good sight lines, and most of my early trips were exactly that. That stops the first time a red light catches the third car.
From then on, following means remembering. The car stuck at the light has lost sight of the leader and is guessing at every turn after that. If somebody in the middle needs gas and pulls off, they’re now driving alone with no idea which road the front car is on. A phone call usually sorts it out, as long as somebody in that car besides the driver can pick up.
The phones keep running the whole time, too. A passenger in the fourth car glances down, sees “faster route available,” and now there’s a debate at highway speed about whether to break off and take it.
After Vermont I wrote a convoy checklist. It had 11 items on it, from app settings to who calls whom when somebody falls behind. I posted it in the group chat on a Tuesday night, feeling pretty good about myself. One friend answered with a thumbs-down emoji and nothing else. Fair enough.
Cutting It Down to One Rule
The rule that survived is that everyone runs the same navigation app. If the lead car is on Google Maps, so is everybody else. The same app with the same settings will usually hand every car the same route when you leave, and I also send a Google Maps link to the exact route in the group chat before we start.
That helps for the first hour or so, and on short drives it’s often enough. On anything longer, each phone still reroutes on its own whenever traffic shifts, and the car that hits the slowdown first gets a new route while the others don’t. My phone and my cousin’s phone were both on Google Maps the following spring, on a drive to Lake George, and we still ended up on opposite sides of the Hudson until the next bridge.
Seeing the Gap While It’s Still Small
You’re back to five separate navigation sessions that have never heard of each other. Regular navigation apps were never built for groups, and I don’t really blame them. Most people drive alone most of the time.
What actually fixed it for us was being able to see the other cars. When everyone joins the same trip in Konvoyage, each car shows up as a dot on one shared map, and the dots update every couple of seconds. The turn-by-turn directions run inside the same app, so nobody is flipping between two screens. If one dot drifts onto a different road, every phone in the group shows it.
On the Vermont trip, those two cars would have peeled off at Brattleboro in plain view. I’d have called them before they were a mile down that state road. They could have turned back, or we could have pulled over at the next exit while they sent a “Wait for me” from the app instead of trying to dial on a road they didn’t know.
We had none of that in Vermont. The back two cars walked in halfway through the vows, my cousin still in his sneakers, holding the dress shoes he never had time to put on.