Bike Radar
Overlay and audio alerts for BLE bike radars. Offline, no account, no cloud.
新版本 1.9.0
A radar that connects but never sends data now counts as off, so the drop alert and the warning for riding without it can sound. Close passes are measured where the vehicle draws level, and readings closing faster than 126 km/h are left out of close passes and peak closing speed. Switching eBike data on or off takes effect at once. New in Experimental: hold the urgent warning for vehicles to the side. Home Assistant: some close-pass and ride values change meaning (see release notes).
Bike Radar shows and sounds what your rear bike radar sees, on top of whatever app you are already running.
A thin strip down the edge of the screen shows each approaching vehicle's distance, closing speed and lateral position. Tiered beeps rise as the closest vehicle gets nearer, and a distinct urgent tone fires when an impact looks imminent - including while you are rolling slowly toward a junction with a fast vehicle behind. A clear chime sounds when the radar sees nothing left within your alert distance.
Everything runs on your phone: no account, no cloud, no analytics. The optional Home Assistant integration publishes ride stats to your own server and nowhere else. Another app on your phone can ask to use your radar, and nothing reaches it until you allow it on a screen naming the app; that handover happens on the device, app to app.
Features:
- Live overlay with per-vehicle distance, closing speed and lateral position
- Tiered proximity beeps, urgent imminent-impact tone, all-clear chime
- Post-ride summary notification: overtakes, close passes, distance, tightest pass
- Front camera/light auto mode by local sunset (one coarse location read per ride)
- Bosch Smart System eBike telemetry, strictly read-only
- Walk-away and forgot-to-lock reminders
- Optional Home Assistant publishing: batteries, close passes, ride summaries
- Sharing with another app on your phone (with your permission): the radar feed, and if you also allow it control of your tail light and hiding the overlay
- Optional on-device capture log for diagnostics, off by default and never uploaded
- English and Spanish
Requires a supported rear radar paired over Bluetooth (pair it once in system Settings) and Android 12 or newer. There is no standard Bluetooth profile for bike radars, so support is per model; the compatibility list on the project's source page says which units work, and the list is short.
A radar that reports distance only is expected to get the approach beeps, the all-clear and an overlay coloured by distance; the per-vehicle speed and side readouts, the urgent tone and close-pass counting need one that also reports closing speed and lateral position. The radar, camera and eBike integrations degrade gracefully: each works without the others.
Bike Radar is a riding aid, not a safety guarantee. It supplements your own attention and mirrors - it never replaces them.
This is an independent open-source project (GPL-3.0-or-later), not affiliated with or endorsed by any radar or eBike manufacturer.
A thin strip down the edge of the screen shows each approaching vehicle's distance, closing speed and lateral position. Tiered beeps rise as the closest vehicle gets nearer, and a distinct urgent tone fires when an impact looks imminent - including while you are rolling slowly toward a junction with a fast vehicle behind. A clear chime sounds when the radar sees nothing left within your alert distance.
Everything runs on your phone: no account, no cloud, no analytics. The optional Home Assistant integration publishes ride stats to your own server and nowhere else. Another app on your phone can ask to use your radar, and nothing reaches it until you allow it on a screen naming the app; that handover happens on the device, app to app.
Features:
- Live overlay with per-vehicle distance, closing speed and lateral position
- Tiered proximity beeps, urgent imminent-impact tone, all-clear chime
- Post-ride summary notification: overtakes, close passes, distance, tightest pass
- Front camera/light auto mode by local sunset (one coarse location read per ride)
- Bosch Smart System eBike telemetry, strictly read-only
- Walk-away and forgot-to-lock reminders
- Optional Home Assistant publishing: batteries, close passes, ride summaries
- Sharing with another app on your phone (with your permission): the radar feed, and if you also allow it control of your tail light and hiding the overlay
- Optional on-device capture log for diagnostics, off by default and never uploaded
- English and Spanish
Requires a supported rear radar paired over Bluetooth (pair it once in system Settings) and Android 12 or newer. There is no standard Bluetooth profile for bike radars, so support is per model; the compatibility list on the project's source page says which units work, and the list is short.
A radar that reports distance only is expected to get the approach beeps, the all-clear and an overlay coloured by distance; the per-vehicle speed and side readouts, the urgent tone and close-pass counting need one that also reports closing speed and lateral position. The radar, camera and eBike integrations degrade gracefully: each works without the others.
Bike Radar is a riding aid, not a safety guarantee. It supplements your own attention and mirrors - it never replaces them.
This is an independent open-source project (GPL-3.0-or-later), not affiliated with or endorsed by any radar or eBike manufacturer.
捐赠
版本
尽管下面提供了 APK 安装包的下载选项，但你应该注意，以这种方式安装将不会收到更新通知，这是一种不太安全的下载方式。 我们建议你安装使用 F-Droid 客户端。
下载 F-Droid-
arm64-v8aarmeabi-v7ax86x86_64该版本需要 Android 12 及以上版本。
此包由原始开发者构建并签名，并保证对应于此源代码 tarball。
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arm64-v8aarmeabi-v7ax86x86_64该版本需要 Android 12 及以上版本。
此包由原始开发者构建并签名，并保证对应于此源代码 tarball。
-
arm64-v8aarmeabi-v7ax86x86_64该版本需要 Android 12 及以上版本。
此包由原始开发者构建并签名，并保证对应于此源代码 tarball。
新版本 1.8.1
"Warn up to" now starts at No limit, so the fastest approaches get beeps and urgent warnings again. In 1.8.0 it started at 126 km/h, which could silence a real vehicle. A speed you chose yourself is kept. To quiet fast phantom readings again, set a speed in Settings → Alerts; 126 km/h was the 1.8.0 setting.
新版本 1.7.1
The Privacy screen now lists what the ride summary sends to Home Assistant, and says it updates during the ride. The example ride, the volume step and Alert sounds explain why the volume buttons can change your wake-up alarm. English and Spanish now use one name each for the all-clear.