My triathlon coach (not a human) now texts me on iMessage

When I started triathlon in 2018, my “training plan” was writing down what I did in Apple Notes and watching YouTube for advice. Later, training for my first full-distance IRONMAN, I paid a coach 130eur/month with the goal to learn early so I could self-coach later. When I switched to a static plan (bought a 40-week one I’d reuse), I started spending 20-30min every Sunday reshuffling sessions around work, travel and private commitments.

In early 2025, training for the 70.3 IRONMAN World Championship, I figured AI would finally fix my biggest pain point: automatically adapting my zones and plan from my activity data. But nothing out there did, and I was reluctant to build it myself (I was determined to build in B2B). A year later, once LLMs had improved a lot, I handed my Sunday planning to Claude, and it worked far better than I expected. Friends wanted to try, so I started shipping it to them.

Hundreds of commits later, I believe the thing that matters most is the data layer. Most “AI coaches” smell like AI slop from a mile away (more often than not, just a ChatGPT wrapper designed in lovable). Not saying our landing page isn’t detectable as Claude-generated, but the core has always been proper integration of wearable and app data (Garmin, Whoop, Hevy, Zwift…) - our core product is essentially an MCP server.

Also, we don’t think the future is apps built for millions (n=∞), but custom (n=1) or conversational products. So we now solve for both: direct MCP access so you can build your own dashboards in your preferred tools, and a coach on iMessage that proactively writes and adapts your plan from your activity and recovery data (it reads 20+ wearables and apps) plus your preferences. Founder tip: connect your calendar, so it picks up travel/commitments automatically.

As a bootstrapped consumer startup, our biggest challenge is pricing (we charge yearly/monthly subscription): consumsers still expect a flat subscription, but our marginal cost is per-message inference. Curious to hear how others handle variable costs in an environment where old (subscription) habits prevail. And what your thoughts are on the future of apps!!