The hardware has been there since 2019.
When Apple released AirPods Pro in 2019, they introduced a surprisingly capable motion sensor that most people never noticed.
Every AirPods Pro contains a gyroscope and an accelerometer. Apple designed them for features like head tracking and spatial audio, but the hardware is capable of much more.
I use those sensors for sports tracking.
The technology has been there since 2019. I simply started looking at it from a different perspective.
Today, Kinapod works with:
- AirPods Pro (2019 version and newer)
- AirPods (3rd generation and newer)
- Beats Fit Pro
No custom hardware.
No modifications.
Just software.
A different way of thinking about AirPods
Don't think of AirPods as earbuds. Think of them as wireless IMUs.
Most applications use AirPods exactly as Apple intended: worn in the ear. Kinapod starts with a different assumption. Instead of treating AirPods as earbuds, I treat them as tiny wireless motion sensors.
That means they don't have to stay in your ears. They can be attached to sports equipment, mounted on a shoe, embedded inside a flying disc, fixed to a racket, or placed anywhere motion needs to be measured.
To the best of my knowledge, this is the first platform built around using AirPods this way.
Once you stop thinking of AirPods as headphones, they become something else entirely: a compact wireless IMU that millions of people already own.
50 Hz is enough
Apple exposes real-time motion data from AirPods at 50 Hz.
At first glance, that doesn't sound particularly impressive. Dedicated sports sensors often sample at a few hundred hertz, and that's generally considered necessary for high-performance motion tracking.
As it turns out, that isn't always true.
Using the same 50 Hz signal, I've already built a running footpod, measured flying disc spin above 1800 RPM, estimated release speed, recognized movement patterns, and computed detailed sports metrics in real time.
One of my earliest running prototypes estimated treadmill pace with roughly 1–3% error.
What's even more exciting is that this result was achieved without training any machine learning models and without tuning the algorithm on recorded running data. The estimate comes purely from signal processing, physics, and carefully designed algorithms. I believe there's still significant room for improvement once machine learning is introduced.
The sensor usually isn't the limiting factor. Modern consumer devices already produce remarkably useful motion data.
The difficult part is figuring out what information is hidden inside that signal. That's where most of the work happens, and that's the part that stays behind the curtain.
Surprisingly long wireless range
One of the biggest surprises while developing Kinapod was wireless range.
In my testing, an iPhone maintained a stable connection to an AirPod at around 60 meters in line-of-sight conditions.
Even more interesting, paired AirPods communicate with each other using Apple's proprietary wireless link. One AirPod effectively acts as a relay for the other, extending communication between the pair to roughly 220 meters in line-of-sight conditions.
That's far beyond what most people expect from a pair of earbuds.
Built for real-time feedback
Sports tracking only works if the data arrives fast enough.
In my testing:
- Typical end-to-end latency is below 150 ms
- Motion data continues streaming in real time without noticeable throttling
- I haven't observed software-imposed limits on accelerometer values during high-acceleration motion
- If the wireless connection is briefly interrupted, the stream automatically recovers once communication resumes
The goal isn't collecting data after your workout. It's giving feedback while you're still moving.
High-speed motion
One of my first questions was whether AirPods could keep up with fast sports.
They can.
The built-in gyroscope comfortably measures rotational speeds above 1800 RPM, making it suitable for rapidly spinning equipment such as flying discs.
For many applications, the sensor performs considerably better than most people would expect from a pair of earbuds.
It actually started with running
Kinapod wasn't originally about frisbee.
Years before Kinapod Disc, I was experimenting with using AirPods as a running footpod.
The question was simple. Could a pair of earbuds replace dedicated running hardware?
Surprisingly, yes.
My prototype estimated treadmill pace with roughly 1–3% error while also measuring additional running dynamics.
Those results were achieved before any machine-learning training or athlete-specific tuning. They came purely from signal processing and physics.
That project eventually led me to a much bigger question. If AirPods can understand running, what else can they understand?
Beyond frisbee
Kinapod Disc is simply the first public demonstration of the platform.
The same technology has potential across many sports, including:
- Running
- Track & field
- Tennis
- Pickleball
- Badminton
- Baseball
- Cricket
- Golf
- Hockey
- Lacrosse
- Skateboarding
- Flying disc sports
- Strength training
The only real limitation is where you can securely attach the sensor, and what meaningful information can be extracted from its motion.
In many cases, that's a software problem rather than a hardware problem. The hardware already exists. The challenge is discovering what it can measure.
Wearables keep getting smarter
Every generation of consumer devices adds more sensing capabilities.
AirPods Pro 3, for example, introduce in-ear heart-rate monitoring alongside the motion sensors that have existed since 2019.
In my own testing, heart-rate measurements have been comparable to dedicated chest-strap monitors such as the Polar H10 for many activities. The primary difference is that AirPods typically report heart rate with roughly 3 seconds more latency.
As consumer devices continue improving, I expect software to unlock capabilities that were never part of their original design. That's exactly what Kinapod is built around.
My vision
I don't think athletes should have to buy a different sensor for every sport.
The sensors already exist.
Phones.
Earbuds.
Watches.
Wearables.
My goal is to figure out what those sensors can actually measure.
Today that's flying discs. Tomorrow it could be racket sports, running, baseball, golf, hockey, lacrosse, skateboarding, track & field, or something nobody has thought of yet.
The only real limit is imagination.
Kinapod Disc is just the beginning. The App Store version currently focuses on flying discs, but it's only the first step. I'll continue expanding Kinapod with support for more sports and more capabilities as the platform evolves.