# Holeshot

> Holeshot is an iPhone app that times car acceleration — 0-100 km/h, 0-60 mph, 100-200 km/h, 60 ft, 1/8 and 1/4 mile, 1 km, and rolling 80-120 km/h / 60-130 mph — hands-free, by fusing the iPhone's 100 Hz motion sensors with GPS. It is for closed courses, drag strips and track days.

Key facts:
- Platform: iPhone (iOS 17+). No extra hardware.
- How it starts: stop the car, the in-app drag tree stages itself and turns green; launch whenever ready. The clock starts on the first movement, detected by the accelerometer.
- Why it's more accurate than GPS-only timers: phone GPS reports ~1 time per second with delay; Holeshot integrates 100 Hz acceleration and fits it to every GPS fix after the run, learning the phone's GPS delay.
- Simulation accuracy: across 300 simulated runs with realistic sensor faults, 0-100 km/h error was ≤0.09 s at the 95th percentile (a GPS-only timer: ~0.6 s typical, >2 s one run in twenty).
- Outputs: timing card with splits, trap speeds, top speed, peak g, road slope (barometer), GPS accuracy, and delta vs personal best per car (purple = new best).
- Dashboards: Christmas Tree, Cluster, Night HUD (with windshield mirror mode).
- Price: first run free; Holeshot Pro $3.99/week, $11.99/month (3-day free trial), $45.99/year.
- Privacy: location and runs stay on the device; only anonymous purchase records (via RevenueCat) leave it; no accounts or tracking.
- Availability: coming soon to the App Store.
- Languages: English, German, French, Spanish, Italian, Portuguese (Brazil), Dutch, Arabic, Turkish, Japanese — localized pages: https://www.getholeshot.xyz/de/, https://www.getholeshot.xyz/fr/, https://www.getholeshot.xyz/es/, https://www.getholeshot.xyz/it/, https://www.getholeshot.xyz/pt-br/, https://www.getholeshot.xyz/nl/, https://www.getholeshot.xyz/ar/, https://www.getholeshot.xyz/tr/, https://www.getholeshot.xyz/ja/.

## Pages
- [Home](https://www.getholeshot.xyz/)
- [Why phone 0-60 apps are inaccurate](https://www.getholeshot.xyz/guides/why-phone-0-60-apps-are-inaccurate/)
- [How to measure 0-100 km/h (or 0-60 mph) with your phone](https://www.getholeshot.xyz/guides/how-to-measure-0-100-with-your-phone/): A step-by-step guide to timing your car's acceleration with an iPhone: mounting, staging, launching, and reading the result — safely, on a closed course.
- [What is 1-ft rollout (and why magazine 0-60 times look quicker)](https://www.getholeshot.xyz/guides/what-is-rollout/): Rollout is the first foot of movement that drag strip timers and US car magazines leave out. It typically makes a 0-60 mph time 0.2–0.3 s quicker.
- [The drag racing Christmas tree, explained](https://www.getholeshot.xyz/guides/drag-racing-christmas-tree-explained/): Pre-stage, stage, three ambers, green and red: how the drag strip starting lights work, the difference between a Sportsman and a Pro tree, and what a red light means.
- [What is a holeshot?](https://www.getholeshot.xyz/guides/what-is-a-holeshot/): In drag racing, the holeshot is winning off the start line: reacting and launching better than the other lane, even with a slower car.
- [60-foot time: what it is and what a good one looks like](https://www.getholeshot.xyz/guides/60-foot-time-explained/): The 60-ft time measures the first 60 feet of a drag run. It is the clearest read on your launch, and every tenth there is worth more than a tenth at the finish.
- [Trap speed: what it tells you that the ET doesn't](https://www.getholeshot.xyz/guides/trap-speed-explained/): Trap speed is how fast you are going at the end of the run. ET reflects launch and traction; trap speed reflects power-to-weight.
- [100-200 km/h: the number that separates fast from very fast](https://www.getholeshot.xyz/guides/100-200-kmh-explained/): Why 100-200 km/h is the favourite benchmark for high-performance cars, what good times look like, and how it is measured.
- [60-130 mph and roll racing, explained](https://www.getholeshot.xyz/guides/60-130-mph-roll-racing/): Roll racing starts from a cruise instead of a standstill. Here is how 60-130 mph, 40-70 mph and 80-120 km/h intervals are timed.
- [Slope and wind: how they change your times](https://www.getholeshot.xyz/guides/slope-and-wind-how-they-change-your-times/): A 1% downhill grade can flatter a 0-100 by a tenth or more. Holeshot uses the iPhone's barometer to measure the slope of every run.
- [Quarter mile vs eighth mile](https://www.getholeshot.xyz/guides/quarter-mile-vs-eighth-mile/): 1/4 mile is 402 m (1,320 ft); 1/8 mile is 201 m (660 ft). How the two relate and why many tracks now run the eighth.
- [GPS performance meters vs phone apps](https://www.getholeshot.xyz/guides/gps-performance-meter-vs-phone/): Dedicated 10 Hz GNSS performance meters are the reference. Here is what they do differently, and how a phone app can close the gap with sensor fusion.
- [Trap speed horsepower calculator](https://www.getholeshot.xyz/tools/trap-speed-horsepower-calculator/)
- [Quarter-mile ET calculator](https://www.getholeshot.xyz/tools/quarter-mile-calculator/)
- [Privacy](https://www.getholeshot.xyz/privacy/)
- [Support](https://www.getholeshot.xyz/support/)
- [Full text for LLMs](https://www.getholeshot.xyz/llms-full.txt)