ClearSpeed GPSGPS speedometer App Store $4.99

HUD setup

Using HUD mirror mode safely

HUD mirror mode flips the speed display so it reflects correctly in glass. Set it up before you move, and use it only if the reflection is easy to read without looking away from the road.

By David Balderston, the app's developer · Updated

See the difference

Readable on the phone, reversed for the glass

Use HUD without Mirror when looking directly at the phone. Turn on Mirror for a windshield reflection: the speed readout reverses on the phone so its reflection can read normally.

Saved HUD screen cropped to show the normal 48 MPH speed readout
HUD · Mirror offThe readout faces you on the phone.
Illustration of the same 48 MPH readout reversed horizontally for mirror mode
HUD · Mirror on (illustration)The phone looks reversed; the reflection reverses it again.

Illustrated comparison: the left is a crop from a saved app screen with sample values. The right reverses that crop to explain Mirror. It is not a new capture or a photograph of a windshield, and it does not demonstrate GPS accuracy or reflection quality. App controls are outside the crop.

Side-view placement diagram: a secured phone sits below the driver's line of sight, with its display reflecting in the windshield. The diagram is illustrative and not to scale.
Placement diagram · not a hardware photo Check from the driver’s seat while parked. Keep the phone secure and clear of your view, airbags and vents. Reflection depends on the glass, lighting and position.
  1. While parked, tap HUD, then Mirror.
  2. Secure the phone and check the reflection without changing your normal driving posture.
  3. If the reflection is faint, doubled or distracting, use Normal with a suitable mount instead. Do not adjust the phone while moving.

Read the full HUD setup and limits · Compare with navigation-app speed displays

Set it up while parked

  1. Open ClearSpeed and wait for Good GPS.
  2. Tap HUD, then Mirror. (Mirror can also be set in Settings → Display → HUD mirror.)
  3. Leave Keep screen awake on (it is on by default) so the display doesn't lock mid-trip. ClearSpeed only measures while it is open on screen.
  4. Start a trip if you want the stats recorded.
  5. Lay the phone flat on a non-slip mat or in a dashboard mount, top of the screen toward you, below your line of sight.
  6. Check the reflection from the driver's seat. If it's doubled, faint, or distracting, switch back to Normal and use a regular mount instead.

Before you drive

  • Do not adjust the app or the phone while moving. Pull over first.
  • Keep the phone clear of airbags, vents, and your view of the road.
  • Follow local laws about phone placement and use while driving.
  • Screens and batteries get hot in direct sun on a dashboard; remove the phone if iOS shows a temperature warning.

Brightness

At night, the default HUD brightness is usually enough. Very bright screens can create glare on the glass. Adjust iPhone brightness before you set off.

Battery

HUD mode keeps the screen on and GPS running. For long drives, connect power. Battery Saver (Settings → Battery) lowers GPS precision and dims non-essential UI to reduce drain.

Not a certified instrument

ClearSpeed is an informational display. Your vehicle's speedometer and posted signs remain the reference.

Try it on your next trip

ClearSpeed GPS is $4.99 once in the U.S. App Store, with no subscription, in-app purchases, or ads. View ClearSpeed GPS on the App Store.

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