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Guides, tips, and insights about GPS speed tracking

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How to Test Your Boat's Real Speed with GPS

How to Test Your Boat's Real Speed with GPS

Your knotmeter and your phone disagree, and neither is broken. Here's how to run a proper boat speed test in knots with GPS, and what the numbers mean.

boat speed test gps boat speedometer speed over ground
August 2, 2026 • 20 min read
Best GPS Speedometer Apps for iPhone (2026)

Best GPS Speedometer Apps for iPhone (2026)

We tested the top iPhone speedometer apps of 2026 — honest picks for the best all-rounder, simplest gauge, best HUD, and best free option.

best speedometer app gps speedometer iphone speedometer app comparison
July 4, 2026 • 11 min read
How Does a GPS Speedometer Work? The Science Behind Accuracy

How Does a GPS Speedometer Work? The Science Behind Accuracy

How does a GPS speedometer work? From satellite signals and atomic clocks to trilateration and Doppler shift — and why GPS speed often beats your dashboard.

GPS technology how GPS works GPS accuracy
October 15, 2025 • 27 min read

All Posts

How to Test Your Boat's Real Speed with GPS

How to Test Your Boat's Real Speed with GPS

Your knotmeter and your phone disagree, and neither is broken. Here's how to run a proper boat speed test in knots with GPS, and what the numbers mean.

tutorials
August 2, 2026 • 20 min read
Best Free Speedometer Apps for iPhone (2026)

Best Free Speedometer Apps for iPhone (2026)

The best genuinely free speedometer apps for iPhone — what you get for $0, where paywalls hide, and which app fits driving, cycling, or scooters.

comparisons
July 9, 2026 • 8 min read
Best Speed Camera Detector Apps for iPhone (2026)

Best Speed Camera Detector Apps for iPhone (2026)

The best speed-camera alert apps for iPhone in 2026, compared honestly: what GPS camera apps can and can't do, and which has the best database.

comparisons
July 4, 2026 • 9 min read
Best GPS Speedometer Apps for iPhone (2026)

Best GPS Speedometer Apps for iPhone (2026)

We tested the top iPhone speedometer apps of 2026 — honest picks for the best all-rounder, simplest gauge, best HUD, and best free option.

comparisons
July 4, 2026 • 11 min read
How Accurate Is a GPS Speedometer at High Speeds?

How Accurate Is a GPS Speedometer at High Speeds?

At 70 mph or 120 km/h, a phone GPS speedometer is typically accurate to ±0.1–0.2 mph — often closer to your true speed than the dashboard. Here's why, and when it isn't.

comparisons
May 14, 2026 • 20 min read
Tire Size and Your Speedometer: How to Find Your Real Speed

Tire Size and Your Speedometer: How to Find Your Real Speed

New tires can shift your speedometer reading by 6 mph at highway speed. Here's how the error works, how big it is, and how to find your true speed in 60 seconds.

tutorials
May 12, 2026 • 18 min read
How GPS Speed Tracking Works Without Internet (2026 Guide)

How GPS Speed Tracking Works Without Internet (2026 Guide)

GPS and the internet are separate systems: your phone just listens to satellites. Here's what works offline (speed, distance, altitude), what needs data, and why offline accuracy is identical.

tutorials
November 25, 2025 • 18 min read
GPS Accuracy on Curves vs Straight Roads

GPS Accuracy on Curves vs Straight Roads

The myth: GPS speed goes wrong on curves. The truth: Doppler keeps your speed accurate through any bend — it's your logged distance that reads short. Here's why the two behave differently.

tutorials
November 2, 2025 • 29 min read
Why GPS Speed Is More Accurate Than Your Car's Speedometer

Why GPS Speed Is More Accurate Than Your Car's Speedometer

Your car's speedometer is legally built to read 3-10% high; GPS measures your true ground speed. Here's why GPS is more accurate, and when the dashboard still wins.

comparisons
October 16, 2025 • 21 min read
How Does a GPS Speedometer Work? The Science Behind Accuracy

How Does a GPS Speedometer Work? The Science Behind Accuracy

How does a GPS speedometer work? From satellite signals and atomic clocks to trilateration and Doppler shift — and why GPS speed often beats your dashboard.

tutorials
October 15, 2025 • 27 min read