Universal Bike Radar

About Universal Bike Radar

Universal Bike Radar turns your phone into a display for a rear-facing bicycle radar. Cars approaching from behind appear on a road strip with their distance and closing speed, and you hear a warning before you see them in the mirror.

REQUIRES A COMPATIBLE RADAR
This app is a display, not a radar. You need a rear-facing bicycle radar that talks Bluetooth LE — W100 and compatible clones, Garmin Varia, Bryton Gardia, Magene, iGPSPORT and others using the same protocols. The hardware is not included.

WHAT YOU GET
• A road strip you can read at a glance: each car keeps its own colour, distance and closing speed
• Sound and vibration warnings, louder and faster the closer a car gets
• A separate red alert for anything approaching fast, with the threshold you choose
• A convoy warning — because after the first car passes, the decision is different
• Works in the background with the screen off and the phone in your pocket
• Standby mode: the screen goes black on an empty road and wakes itself when the radar sees a car
• Orientation lock, so a phone in a handlebar mount stops flipping

ONE KNOB THAT MATTERS
Alert sensitivity runs from 1 (only what is truly urgent) to 5 (every car announced), and you can change it with one tap on the ride screen without opening settings. The levels were measured on hours of real radar recordings, not guessed: on the same city ride level 1 plays 2.2 warnings per minute and level 5 plays 16.

QUIET WHEN IT SHOULD BE
Warnings that carry no information are removed on purpose. Cars that are moving away do not beep. A car that has already passed goes silent instead of trailing five more beeps. In dense traffic, where something is behind you all the time, the routine ticking stops — the red alerts and convoy warnings keep playing, because those tell you something you do not already know.

FREE, AND A COFFEE IF YOU LIKE IT
Detection, warnings, background operation, muting, vibration, ride recording and the paired radar are free and stay free. The free version runs on one alert preset, "Standard", deliberately the middle of the scale.
A single optional purchase — buy me a coffee — unlocks the other sensitivity presets, manual alert tuning, alert tones, appearance options and ride history. One payment, no subscription, no ads, ever.

PRIVACY
No accounts, no ads, no analytics, no servers. Nothing leaves your phone unless you press "Send" on a recording yourself.

SAFETY
A radar is an aid, not a substitute for looking behind you and riding predictably. Set the app up before you ride, mount the phone properly, and keep your eyes on the road.