LapTAR — the lap timer that tells you which corner cost you

Turn 1 cost 0.28 s.

Scroll through it. Every turn is split into the brake, the trail, the turn and the exit, and each part gets two answers: time against your optimal lap, and how much of the car you used.

Delta+0.00

km/h000

Lap clock 0:03.0

And it tells you, in your ear.

0:55.6Next left. Brake 30 metres later.

1:10.2Better.

What the coach said on this lap: one instruction before turn 7, picked from the laps before, and the verdict once the corner was done. Turns go by their direction, so you never count corners at 180 km/h.

Measured against the lap you already drove.

Your optimal lap is your own best corners, joined on the straights, and never slower than any lap you did. No ghost of a faster driver: the gap is time you have already found once.

This lapLap 3 of 25
2:11.786
Session bestLap 22
2:10.500
OptimalBest corners of all 25 laps
2:09.136

The live gap to the optimal through lap 3, as the screen showed it. It never got ahead: where the line rises time went, where it dips a corner won some back. The gap compares the two laps at equal distance, and lap 3 measured 17 m longer than the optimal, so at the line it reads +2.18 s, not the 2.65 s between the two lap clocks.

Your phone is the timer.

Mount it, start a session, drive. Everything else adds channels; nothing else is required.

GPSIn the phone
Lap times, the live delta, speeds and every corner verdict, from the phone alone.
VoiceIn the phone
The call before a corner and the verdict after it, through the speaker or your helmet headset.
OBDOptional
A Bluetooth OBD adapter adds throttle, brake and RPM to every lap.
OverlayIn the app
Export any lap as a transparent overlay for your onboard footage.
HistoryIn the app
Import RaceChrono sessions, follow every turn across track days, and keep a setup sheet with each lap.

Turn 1 cost 0.28 s.

And it tells you, in your ear.

Measured against the lap you already drove.

Your phone is the timer.

Next session, coached.