How to Use HUD Mode: Mirror Your Speed onto the Windshield (Pro)

TL;DR

HUD mode shows a mirrored speed readout at full brightness so its reflection reads correctly on the windscreen. It is green while you are clear and red over the posted limit. Controls fade out; a tap brings them back. Pro only.

The problem

Looking down at a phone to check your speed takes your eyes off the road. Commercial head-up displays cost money and wiring, and a normal app screen is too dim and the wrong way round to reflect.

Setup

  1. Unlock SpeedTrace Pro.
  2. Place the phone flat on the dashboard, screen up, under the windscreen where you can see the reflection without moving your head.
  3. Open HUD from the speedometer.
  4. The speed is mirrored, the screen goes to full brightness, and the controls fade so only the number shows. Tap the screen to bring them back.
  5. Use the orientation lock in the corner to freeze the layout if the phone wobbles between portrait and landscape on bends.

Colours

  • Green while you’re clear. It reads well against glass at night.
  • Red when you exceed the posted limit (needs Show Speed Limit on and a limit known).

Safety

Mount or place the phone securely and set it before you move. A phone on a dash can slide on bends and in a crash; use a non-slip mat. Check local law: some places restrict dashboard devices. Use at night; sunlight washes out the reflection.

Battery

Full brightness and GPS drain the battery, so plug into power.

FAQ

Is HUD free? No. HUD mode is part of SpeedTrace Pro.

Why is the text mirrored? So that the reflection in the windscreen reads the right way round.

When does it turn red? When you exceed the posted limit, if Show Speed Limit is on and a limit is known.

Does it work in daylight? It is designed for night. Reflections are faint in strong sun.

The app SpeedTrace →