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Android Exclusive

Your ultimate destination for precise sprint timing.

Turn two Android phones into a synchronized timing system. Dramatically more consistent than a hand-timed stopwatch — no lab hardware required.

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Free to start • Requires 2 Android devices
Sprinter driving out of the starting blocks on a track
Our Philosophy

We're passionate about honest speed data. We believe elite-level measurement shouldn't be locked behind prohibitive hardware costs.

Lane lines on an empty running track
The Toolkit

One app. Four tools.

Flagship Feature

Timing Gates

Two Android phones become synchronized start and finish gates. Automated splits and reaction off the start cue.

  • Synchronized start & finish gates
  • Automated split times
  • Reaction time off the start cue
  • Computer-vision finish detection
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±0.022s
Validated timing consistency
Kinematics

Sprint Form Analysis

Upload a sprint video and get frame-by-frame AI biomechanics — joint angles, stride cues, and technique scores.

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Plyometrics

Jump Measure

Vertical jump height from flight time. Import a clip, get your numbers — no jump mat required.

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Neural

Reaction Pro

Train and measure your sprint-start reaction time with drills and trend tracking.

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Athlete reviewing sprint timing data on a phone at the track
Premium Tools

Pro-grade analysis in your pocket.

By linking two Android phones, SpeedTrackr eliminates the human error of a human thumb on a stopwatch. Get automated splits, highly consistent reaction times, and objective timing data.

  • Reaction time detectionDetects the reaction time from the sound of the audio trigger.
  • Computer-vision finish lineAnalyzes video frames to log the exact crossing moment.
10.75s
Founder 100m PB, hand-timed
±0.022s
Validated timing consistency
$0
Upfront hardware cost
Cinematic view of a running track at golden hour

“Each session, carefully measured for real performance.”

Process

Enjoyable, precise timing every time.

Place & Connect

Position one Android phone at the start line and one on a tripod at the finish. Pair them instantly with a simple 4-digit code.

Auto-Sync Clocks

The devices automatically synchronize their internal clocks over the air — dramatically more consistent than a hand-timed stopwatch.

Run & Time

Sprint through. The start device listens for your starting cue and the finish gate detects your crossing with computer vision, calculating splits instantly.

Cost-effective measurement

Pro-grade timing, zero hardware debt.

Ditch the heavy tripods and expensive proprietary sensors. You likely already own the hardware you need.

Dedicated Hardware

Laser gates, jump mats, reaction lights

Upfront Cost$400–$2,500
PortabilityBulky tripods & cases
Setup Time~15 minutes

SpeedTrackr

Dual-phone software system (Android)

Upfront Cost$0 (Free to start)
PortabilityFits in your pocket
Setup TimeUnder 60 seconds
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Origin

“I wanted real numbers instead of a human thumb on a stopwatch.”

After 14 years of competitive sprinting in Chennai, the difference between a good day and a bad day came down to hundredths of a second — but real biomechanical feedback meant expensive labs and elite specialists I never had access to.

So I built SpeedTrackr: honest measurement from the processing power already in our pockets. Now I'm using it on myself, publicly — a 52-week program with every session logged and every time trial published.

Dafin Edison, founder of SpeedTrackr
Dafin Edison
Sprinter & creator of SpeedTrackr
Founder's 100m PB — hand-timed
10.75s
100m DashTarget: 10.50s · May 2027
The 52-Week Experiment

Follow the live journey — every session logged, every number public.

Latest from the track

Practical guides to convert insights into results.

Frequently asked questions

Everything you need to know about setting up and trusting the system.

How accurate is the synchronization?
The dual-phone system has been validated to a timing consistency of ±0.022 seconds — dramatically more consistent than a hand-timed stopwatch, because it removes the human reaction variable from your session data entirely.
What makes SpeedTrackr different from generic fitness apps?
SpeedTrackr is a dedicated sprint training suite. Unlike generic fitness apps, it connects two standard smartphones over the air to build a high-precision wireless timing gate, combined with AI video biomechanics analysis.
Is SpeedTrackr built for solo athletes?
Yes. SpeedTrackr is designed specifically for individual sprinters, track athletes, and field sports players to set up, run, and time their sessions entirely on their own.
How does pricing work?
SpeedTrackr is free to start. Premium subscriptions unlock unlimited timing sessions and AI analysis credits — everything is managed inside the app.
What hardware do I need?
Two modern Android smartphones. A cheap mini-tripod helps hold the finish phone steady, but many athletes simply lean it against a water bottle or bag.
Is an iOS version available?
Currently, SpeedTrackr is an Android-exclusive application. This lets us focus deeply on optimizing the connection protocol between the two devices.

Ready to lead the field?

Download SpeedTrackr for Android today and bring precision timing to your next speed session.

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