GitHub
rehalo is an independent, open-source app that brings the ring on your handlebars back to life. It's on iPhone today, and an Android app is planned. Just your bike, your phone and the ring.
The company behind the ring ran out of cash and closed. The servers the devices relied on went with it.
The front light and the alarm still worked. The rest stopped working properly, and a good piece of hardware was left on thousands of handlebars with nothing to talk to.
The firmware was published so a community could keep the devices going. People documented the API and took the ring apart. That work is why this exists.
rehalo started from that source code. It read the ring's Bluetooth language line by line and rebuilt the app around it, with one rule: this time, nothing depends on a server that can disappear.
What's back
Every animation below is the ring's own. They're ported from the firmware source and checked against it, LED by LED and frame by frame. Long stretches of a ride are shortened here.
Load a GPX route or search for a place. Near each turn an arc lights up on the side you'll turn, fills green from its centre as you get closer and blinks when it's time. The small display shows the street, and the whole ring pulses green when you arrive.
Go off route and an orange pointer leads you back.
Compass mode skips the route. A pointer holds the direction of your destination and shifts from orange to green as you get closer. The streets are up to you.
Walk away and the Halo arms itself, then goes dark. Move the bike and orange arcs warn you off, then the alarm sounds and the ring strobes. Come back with your iPhone and it stands down. Phone dead? Tap your five-beat code on the ring.
The app tells you how many times the alarm went off while you were away.
Clock, battery, speed, distance, ride time and average speed, one swipe apart on the ring. Short and long taps trigger the horn, the light or a quick reading.
The whole ring pulses blue and the display shows the call. One short tap silences it.
iOS doesn't say who is calling, so neither can we. It works while you ride or navigate.
The storm icon has been sitting in the firmware all along, and the official app never used it. Now, if rain is due within half an hour, the ring pulses a deeper blue and shows the storm icon for about six seconds. It warns you once, and waits if you're about to turn.
Off by default. Forecasts come from Open-Meteo, with no key or account.
Better than it was
A guided wizard reclaims a Halo whose password died with the old app, and your new password is backed up in your Keychain.
Demo mode simulates the Halo and the ride, so you can explore everything first.
Far from your route? rehalo offers to lead you to the start or to the nearest point on it.
No server to lose
| What | Goes through | Account needed |
|---|---|---|
| Controlling the ring | Direct Bluetooth | None |
| Maps, search, directions | Apple Maps, so these need internet | None |
| Rain alerts | Open-Meteo, only if you turn them on; location rounded to about 1 km | None |
| Ride sync | Your own server, if you want one | Yours |
| The original company's servers | Never | None |
Open to evolve
rehalo is young. It has spoken to a real ring and the app is built, and now it needs real roads. Every feature below shows its true status.
Got a Halo in a drawer? Tell us. Every ring on the road makes this better.
The SmartHalo 2 and an iPhone on iOS 17 or later. An Android app is planned. The first-generation SmartHalo is a different design and isn't supported.
rehalo isn't on the App Store yet. For now it's installed by sideloading with your own Apple ID, using a tool such as SideStore.
Yes, that's what the recovery wizard is for. A quirk of the firmware means the ring has to reboot once, and if its battery won't run down that can mean opening the case to disconnect it.
