Film one length from the side. Llyr follows your body through the stroke and tells you what to change, in words you can take back into the water. Where the water hides a joint, it leaves that line blank instead of making it up.
One phone, propped at the sideNothing to strap onReads you as you moveAnalysis runs on the phone
Solid is what Llyr could see above the water.169° is his lead arm, worked out from those points.Hatched is under the water. Llyr couldn't see it, so it drew nothing.
What one camera can see.
Can see
All four strokes
Freestyle, backstroke, breaststroke and butterfly. Each one has its own rules and its own cycle.
Can see
Your body line through the whole cycle
Joint angles in every frame, not one screenshot of the moment something felt off.
Can see
Faults that keep coming back
Llyr has to see a fault more than once before it says anything, so one bad length never becomes a verdict.
Can't see
Whatever the water hides
The tracker was built for bodies above water. When the water takes a joint, Llyr drops it instead of guessing.
You don't have to film live. Import a clip you already
have and step through it a frame at a time — that works for every
sport, not just this one.
Mid-2026All four strokes plus dives, picked before you film. Run and Golf
still read “soon” here — both have shipped since.
Four moves, one length.
1
Set up
The app talks you through it: phone on a bag or a rail, square to the lane, whole body in frame.
2
Record
Hit record and swim. If the framing is off, it tells you before you waste a length.
3
Analyze
One tap. Llyr follows your joints through the whole stroke and works out where in the stroke you are, frame by frame.
4
Correct
The fix lands on the screen you're already watching, and Llyr keeps a still of each one so you can check it later.
The waterline is the point.
Joints, followed frame by frame
Angles are read right through the stroke, so a fault has somewhere to turn up.
Above and below
There's an underwater mode for a phone in a housing. Either way, Llyr works out the camera angle for you.
A target shape to work against
A dashed outline of the shape you're aiming for, drawn next to your own. You can see the change instead of imagining it.
Nothing leaves the phone
Analysis runs on the device. Your footage stays yours.
What we can promise today.
In early access
Nobody has used Llyr long enough to quote, so there are no reviews on this page. When early-access swimmers have something real to say, it will appear with their name on it.
If it can't see it, it says so
When a joint isn't clearly visible, the read stays empty instead of
filling in. The same rule governs this page: no invented praise and
no invented figures.
Measured, not assumed
Corrections come from angles the camera actually got. If a claim would need a second camera or a sensor, Llyr doesn't make it.
Judge it yourself
Join the list, film one session, and hold what Llyr draws against what you already know about your own swimming.
Know what your stroke is doing.
Join the early-access list. Sign up here and swimming is what you'll hear about.
100Seats in the first group
That is the whole of it. We would rather have a hundred people
actually filming and telling us what broke than a list of ten
thousand who never open it.
No spam. Just an email when there's something to try.
