Can you time laps on a circuit with an iPhone?

Yes. ST1 Track uses your iPhone GPS to detect line crossings and record laps, sectors, speeds and braking — without a dedicated box.

Do you need an Alfano, AiM or RaceBox for a track day?

Not necessarily. A 25 Hz box still makes sense if you want dedicated GPS accuracy, an IMU or engine sensors. To know your lap time, sectors and progress from the first track day, an app like ST1 Track is often enough to start.

Is ST1 Track more accurate than an AiM, Alfano or Garmin?

No, and we do not claim that. 25 Hz GPS boxes, dedicated IMUs and ECU connections exist for a reason. ST1 Track is the alternative in your pocket: you start without buying hardware.

How do I create a circuit if it is not in the app?

Drive it. ST1 Track can create the layout automatically from your session, then you find it again for the next days.

Does ST1 Track work in a car, on a motorcycle and in karting?

Yes. The app is built for different vehicles. Once the timer is running, the goal is the same: go faster next lap.

Yes. ST1 Track is currently available for free on iPhone.

Circuit lap timer app · iPhone

Time your laps on track without buying a dedicated box

Your phone is already in your pocket.
So is your lap timer.

No box to buy. No sensor to fit. Pick your circuit, launch ST1 Track and drive.

Download on iOS Discover ST1 Track →

Compare with GPS boxes ↓

Before buying a box, see what your phone already does.

To time, analyse and compare your sessions, you may not need anything more than your iPhone.

Comparison of ST1 Track, RaceBox, AiM, Alfano and Garmin
Feature	ST1 Track	RaceBox	AiM	Alfano	Garmin
Hardware to buy	None	Box	Box	Box	Box
Indicative hardware cost	$0	≈ $289	≈ $500	≈ $460	≈ $1,200
Automatic lap timing	✓	✓	✓	✓	✓
Sector times	✓	✓ / app	✓	✓	✓
Session history	✓	✓ / app	✓	✓ / app	✓
Analysis on phone	✓	✓	via software / apps	via ADA	✓
Circuits / discovery	✓	✓ / app	built-in database	built-in database	built-in database
Create a track	✓	depends on app	configurable	depends on app	✓
Leaderboards	✓	depends on app	—	—	✓

Swipe right to see AiM, Alfano and Garmin.

Indicative prices from manufacturer list prices, shown in the local currency. Actual prices vary by country, retailer and taxes.

Your phone is already in your pocket.

So is your lap timer.

Try ST1 Track for free →

Nürburgring

Amateur Nordschleife

8:52.140

Current lap

Laps

214

km/h

−2.1

Delta

GPS Active

The circuit in your pocket

You open it. You see where to drive. You choose. You time laps. You analyse. You compare.

01
You find it
Circuits around you appear. Switzerland, France, Germany, Italy, and farther. You pick your track.
02
You drive
GPS detects line crossings. Your laps record themselves. No sensor to stick on, no box to power.
03
You analyse
Sectors, speeds, braking zones: see where you gain, and where you lose.

Then you compare. Every circuit has a leaderboard: your time, your car, your position.

Automatic creation

The circuit is not in ST1 Track?

Drive it. Now it is.

No need to drop a finish line by hand on a satellite map. You drive, the layout is created from your session — private track, karting, or a circuit still missing from the database.

Lap timer apps already exist.

And that is exactly the problem we wanted to solve differently.

ST1 Track was not built only to start a timer. You discover where to drive, choose your circuit, record your laps, analyse your sectors and compare your performance.

And if the track is not there yet?

You drive it. Now it exists.

Not a stopwatch in your phone.

The circuit in your pocket.

You don’t need a $460 box yet.

Start with what you already have.

Do your first sessions.

Learn your lap times.

Understand your sectors.

Improve.

And the day you need ECU telemetry, dedicated sensors or 25 Hz GPS, you will know exactly why you are buying extra hardware.

Circuit lap timer for cars, bikes and karting

A lap time is a lap time. It does not matter what you bring to the track.

Car lap timer on circuit: GT during a night track session

Car

Track days, club sessions, circuit hire.

Motorcycle

Laps, sectors and braking, with no box on the fairing.

Karting

Stack sessions and track your progress.

Frequently asked questions

Can you time laps on a circuit with an iPhone?: Yes. ST1 Track uses your iPhone GPS to detect line crossings and record laps, sectors, speeds and braking — without a dedicated box.
Do you need an Alfano, AiM or RaceBox for a track day?: Not necessarily. A 25 Hz box still makes sense if you want dedicated GPS accuracy, an IMU or engine sensors. To know your lap time, sectors and progress from the first track day, an app like ST1 Track is often enough to start.
Is ST1 Track more accurate than an AiM, Alfano or Garmin?: No, and we do not claim that. 25 Hz GPS boxes, dedicated IMUs and ECU connections exist for a reason. ST1 Track is the alternative in your pocket: you start without buying hardware.
How do I create a circuit if it is not in the app?: Drive it. ST1 Track can create the layout automatically from your session, then you find it again for the next days.
Does ST1 Track work in a car, on a motorcycle and in karting?: Yes. The app is built for different vehicles. Once the timer is running, the goal is the same: go faster next lap.
Is ST1 Track free?: Yes. ST1 Track is currently available for free on iPhone.

You already have an iPhone.

You already have your lap timer.

Download ST1 Track for free

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