# ZT3 Wheelie · Wheelie assist app for the ZT3 Pro D

> ZT3 Wheelie is a proprietary Android app (Android 8.0 and later) for a wheelie assist on the Segway-Ninebot ZT3 Pro D. An ESP32 with an MPU6050 motion sensor reads the scooter's tilt 1000 times per second; the app connects to it over Bluetooth LE with a six digit PIN and an encrypted link and shows the attitude as a 3D model, the wheelie angle against an adjustable limit, g-forces and a ten second history. It updates itself from this page. Use on private ground only.

This is the Markdown version of https://zt3-pro-wheelie-control.celox.io/ for agents and text tools. A short summary with every link lives at https://zt3-pro-wheelie-control.celox.io/llms.txt.

## Download

- **Newest release:** https://zt3-pro-wheelie-control.celox.io/download (picks the file for your platform; always the current release)
- **Current version:** 0.5.0 · released 2026-09-28
- **Release data as JSON:** https://zt3-pro-wheelie-control.celox.io/latest.json
- **Requirements:** APK: Android 8.0+

Files in the current release:

- APK: https://zt3-pro-wheelie-control.celox.io/download/android (zt3-wheelie-v0.5.0.apk, 1.4 MB)

## Features

- **Attitude in 3D** — A model of the sensor board turns with the scooter. Accelerometer and gyro are fused with a Mahony filter, so the angle stays calm while you ride.
- **Wheelie angle and limit** — Set the zero point with both wheels down, pick the axis the scooter tilts around and set your limit. The side view turns amber near it and red above it.
- **G-forces** — Total acceleration, the part without gravity, the peak and an X/Y plot with a one second trail show accelerating, braking and bumps.
- **Encrypted Bluetooth** — Each controller makes its own six digit PIN and shows it only over USB. Without it no phone can pair, read data or send commands.
- **Honest data** — Only complete lines inside the sensor's range are used. Corrupted lines are counted and dropped, never shown as values.
- **Updates itself** — The app checks this page, downloads a new version, verifies its SHA-256 and hands it to Android's installer.

## Install

1. **Download the APK** — One file for every phone with Android 8.0 or later.
2. **Allow the install** — Open the file. Android asks once whether your browser may install apps, allow it.
3. **Pair the controller** — Open Devices, search, tap ZT3-Wheelie-XXXX and enter the PIN. Read it once over USB with the command `pin`.

## Verify

- `zt3-wheelie-v0.5.0.apk` — SHA-256 `37bade7ecbc1c658c2dafdb61a2b94d7613b098865f8a49fdc44490ffb2ea57f`
- Signing certificate SHA-256: `0e672ef6dc012b6d1824609489db9ce155aecf32a6d881b379b7cb30fe394dde`
- Every release is signed with the same key. Compare with `apksigner verify --print-certs`.

## FAQ

**What do I need besides the app?** The ZT3 Wheelie controller: an ESP32 with an MPU6050 motion sensor, mounted on the scooter and running the matching firmware. Without it the app has nothing to show.

**Does the app control the throttle?** Not yet. Today it shows and configures. The throttle limit is a later phase, and it will only ever reduce the throttle, never raise it; braking always passes through unchanged.

**Where do I get the PIN?** Connect the controller over USB and send `pin`. It is created at random on first start and never goes over Bluetooth. `pin new` makes a new one and forgets all paired phones.

**Is it free?** Yes, free to use for personal, non-commercial purposes, without ads, account or tracking. The software itself is proprietary, all rights reserved.

**Why is it not on Google Play?** It is a companion to self-built hardware. The APK on this page is signed with a fixed key; the app updates itself from here and checks every download against its SHA-256.

**Which phones work?** Any phone with Android 8.0 or later and Bluetooth LE. The app asks for the Bluetooth permission and, for update notices, the notification permission.

## Limits

- Android only; not on Google Play, distributed as an APK from this page.
- Needs the ZT3 Wheelie controller (ESP32 with MPU6050) running the matching firmware.
- The app shows and configures; it does not limit the throttle yet. That is a later phase of the project.
- Connected only while the app is open; there is no background service.
- Yaw comes from the gyro only and drifts slowly.
- The data stream has 50 lines per second; short impacts between two lines are not shown.

## Links

- Source code: https://github.com/pepperonas/zt3-pro-wheelie-control-releases
- Changelog: https://zt3-pro-wheelie-control.celox.io/changelog.md
- Licence (Proprietary): https://github.com/pepperonas/zt3-pro-wheelie-control-releases/blob/main/LICENSE
- Support the project: https://www.paypal.com/donate/?business=martin.pfeffer@celox.io&currency_code=EUR&item_name=ZT3%20Wheelie
- Author: Martin Pfeffer, https://celox.io — Imprint https://celox.io/impressum/ · Privacy https://celox.io/datenschutz/