See it in action
Your personalised technique report.
Film your freestyle, upload it, and get a detailed breakdown of your technique reviewed by a real coach.
Tumbl watches your freestyle and tells you what matters most.
Film it. Upload it. Get better.
We'll keep you posted.
See it in action
Film your freestyle, upload it, and get a detailed breakdown of your technique reviewed by a real coach.
What swimmers say
“I could go to the pool right now and work on it. Genuinely thrilled with how clear and specific the feedback was.”
J.G. — March 2026
“I used the coaching cue during a swim and it had a real impact. The first-use takeaway was immediately useful.”
A.L. — March 2026
“Very well presented and already provided a lot of value. The drills helped me focus on the right thing. Felt like real progress.”
T.H. — March 2026
How it works
No complicated setup, just your phone and a pool.
Get someone to film your freestyle from the side of the pool.
Upload the video to Tumbl. We start analysing straight away.
Personalised technique feedback reviewed by a real coach.
What happens behind the scenes
Every video goes through two stages. Technical analysis using neuro-symbolic architecture, then a real coach review. So you understand what's happening in your swimming and why it matters.
Layer one
Tumbl checks over 40 areas of your freestyle. Catch, pull, kick, breathing, rotation, timing, and more.
Layer two
A real coach reviews your results, adds their expertise, and helps you prioritise what matters most.
Who it's for
You don't need to be fast. You just need to want to get better.
Swimmers who want to improve but don't have access to a private coach.
Coaches who want a tool to give more detailed feedback to their swimmers.
Triathletes, masters swimmers, club swimmers, keen improvers.
Anyone who's ever finished a swim and thought “am I even doing this right?”
About
Hi, I'm Char. I love swimming. I've spent most of my life in the pool, first as a junior elite swimmer and then as a coach.
The thing I notice most, coaching adults every week, is how many swimmers are stuck. They work hard, but they can't see what they're doing in the water and they've got no way of knowing what to focus on.
Getting someone qualified to watch your stroke can often cost £100-200 per analysis. That prices out most people, and even if you can afford it, you get feedback once and then you're on your own again.
I work in tech, and I kept coming back to this idea that there had to be a way to get good feedback to more swimmers, more often. That's what I'm building with Tumbl.
Find out more about the philosophy behind Tumbl →Tips, updates, and first access when we launch.
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