Marine speed is often discussed in knots, while road speed is often MPH or KM/H. A useful GPS speedometer app should make switching units easy and keep the display readable outdoors.

Why knots matter

Knots are commonly used for boats and marine conditions. ClearSpeed GPS includes knots as a built-in unit, alongside MPH and KM/H, so the same app can be useful on roads and on water.

What ClearSpeed GPS can show

GPS signal still matters

GPS performance depends on device placement, signal quality, sky visibility, movement, and environmental conditions. Keep the phone secure and use the signal indicator before trusting the displayed number.

Not a navigation or safety system

ClearSpeed GPS is a speed display. It is not a chartplotter, navigation system, emergency device, or certified marine instrument. Use appropriate marine equipment and follow local rules.

Simple speed in knots

ClearSpeed GPS is useful when you want a clean iPhone GPS speed readout in knots without subscriptions, accounts, ads, or tracking.

Find ClearSpeed GPS on the App Store

Related: choosing MPH, KM/H, or knots and how GPS speedometers work.

Back to GPS speedometer guides