Tail End Charlie

Offline-first group riding

Nobody gets
left behind.

Tail End Charlie keeps the drop-off system simple: one route, a clear marker handoff, and a group view that keeps working when the signal does not.

See how it works View the project

Development alpha for iPhone and Android.

A Tail End Charlie route map showing the TEC gap and group mini-map.
TEC gap Charlie is with the group
One shared routeon every rider’s phone
Clear marker handoffsfor second-bike drop-offs
Local-first updateswhen coverage is patchy

Made for the real world

The simple system you already use, made visible.

A rider marks the junction. The group passes. The TEC collects the marker. Tail End Charlie keeps that shared picture in the background, so the ride can keep flowing.

  1. 01

    Start together

    Create a ride, share a six-digit code, and load the route before you set off.

  2. 02

    Mark with confidence

    The marker view records passing riders and shows when the TEC is approaching.

  3. 03

    Keep the group in view

    See group progress, hazards, and sustained off-route alerts on the live map.

Group awareness

See the route, the riders, and the ride ahead.

The map brings route progress, the lead, the TEC, and the rest of the group into one calm, glanceable view.

A group overview map with riders spread across a road-following route.

Marker mode appears when you need it.

A focused overlay makes the handoff obvious, without losing the map beneath it.

The junction marker handoff view showing that the TEC has passed.

Useful alerts, without the noise.

Riders can flag a problem, leaders can see a confirmed off-course alert, and everyone has a simpler view of what needs attention.

The Tail End Charlie awareness screen with a roadworks hazard and a coordinator alert.

Built around the ride

Less screen time. More road time.

Heading-up navigation, automatic marker prompts, a big rider alert, and a mini-map for the group are designed to be read at a glance and left alone while moving.

  • Road-following GPX routes and downloadable map areas
  • Navigation handoffs for Calimoto, MyRoute-app, Google Maps, and more
  • Optional nearby relay alongside the online group service

Early access

Built in the open, tested on real rides.

Tail End Charlie is in active development. The current build is for controlled testing, not emergency coordination. Field testing will decide what reliability claims it earns.

Follow development iOS TestFlight and Android testing are being prepared.