It reads your body. We only count your day.

Two fitness apps with .ai in the name, both on iPhone, both reading Apple Health. It would be reasonable to assume they are competitors. They are not, really — and this post exists mostly to explain why.

Does ftns.ai read my health data the way SensAI does?

No, and this is the single most important thing to get straight about us. The .ai in ftns.ai is a domain name, not a description of what the app does with your body.

SensAI is a coaching app in the fullest sense the category currently supports. Its materials describe a coach that reads heart-rate variability, sleep quality and resting heart rate through Apple HealthKit — from the Watch directly, and from Garmin, Oura and WHOOP by way of HealthKit — and regenerates your weekly programme from what you actually did and how you actually recovered. You can talk to it mid-session in plain language: shorten this, my shoulder is off, swap this machine. It explains its reasoning back to you.

ftns.ai does not do the reading half of that at all. It never interprets a health metric. It does not have an opinion about your heart-rate variability and does not try to acquire one. Nothing in the app tells you your recovery is low, your readiness is poor, or that today should be a lighter day.

That distinction matters more than it sounds, because an app with .ai in its name in the Health & Fitness category invites exactly the opposite assumption. Your synced steps, workouts and sleep are game inputs here. The output is a character state, not an assessment.

But there is a coach in ftns.ai. What does it actually do?

It plans, and it talks. Being straight about it is more useful than a clean-sounding denial.

The coach builds workout plans from your goal, your pace, the equipment you have and the exercises you have ruled out, and meal plans across six styles with per-meal macros. You can ask it things in plain words — swap a lift you hate, ask how today is tracking — and you pick whether it talks to you in a motivational or a matter-of-fact tone. Finished plans wait in an inbox until you decide to add one; nothing lands in your day on its own.

What it does not do is the load science or the physiology. It does not estimate your one-rep max, do the plate maths, model fatigue, periodise a block, or change your training because your sleep was bad. It is a game feature, not a health professional. It makes no medical claims and promises no results.

If you want an app that reasons about your recovery and moves your training accordingly, that is a genuinely useful product, and SensAI is built for it. It is not something we do — well or badly.

Which one shows you the future?

Both do, in completely different senses.

The SensAI forward view is about the next session and the coming week: what your body can handle now, given how you have recovered.

Future Self is about the year. Your twin rendered across six horizons and three timelines — Current Pace, On Plan and Coasting — as a character you can look at. Free, unlimited, and it never costs gems.

It is a game feature, not a forecast. It does not predict anything about your health, it guarantees nothing, and it does not tell you what will happen to your body. It shows you a version of your character built from the way you are currently playing. How the six horizons work.

Your twin updates weekly, not daily. If one bad night visibly changed your character, the model would be lying to you and you would stop believing it by week two. The whole value of a readiness app is reacting to today. Ours is in refusing to.

Side by side

SensAI details per its App Store listing and sensai.fit, checked 24 August 2026. Several figures come from SensAI published materials rather than independent sources and are treated here as their claims, not as verified facts. Prices change — check your own checkout.

What ftns.ai is not

Stated plainly, because the category invites the assumption:

• Not a training-optimisation engine. The coach plans sessions. It does not estimate your one-rep max, do plate maths, model fatigue or periodise a block. Apps built for that do it better, and this post says so out loud.
• Not a health intelligence. The .ai is a domain. Your coach is a game feature, and it makes no medical claims and promises no results.
• Not a medical or assessment product. ftns.ai is a game in the Health & Fitness category. It doesn't diagnose anything, doesn't give clinical advice, and doesn't tell you what any of your numbers mean about your health.
• Not social. No social feed, no friends list, no leaderboards, no follower count. Sharing means you export a score card yourself, to wherever you like, when you feel like it. The app never posts on your behalf.

On privacy, both apps have a position

SensAI states that raw HealthKit data stays on your device, that aggregated recovery metrics go server-side to inform the coaching, and that it does not sell user data. That is a clearer position than most of the category takes, and worth reading in full on their own site.

The ftns.ai position: your logs, your measurements, your twin and your scores live on your device, not in an account on our servers. Photos are optional — your twin works from your metrics alone — and if you do add the posed shots during setup they are processed in memory only, never stored on our servers, never used to train AI, and discarded the moment your twin is built. Your photos are private and never posted publicly, and there is nothing stored to delete. Settings → Account → Delete everything removes the rest in one tap.

And there is no screen anywhere in the app where your twin appears next to someone else's, because there is no such screen to build one into. Where your data actually lives.

So which one

• Use SensAI if you wear a watch or a ring, you want training that changes when you have slept badly, and you want a coach that can explain its reasoning when you ask.
• Use ftns.ai if you do not want an app making calls about your body, you want the whole day to count rather than the session, and the thing you need is a reason to show up.
• Use both if you want recovery-driven coaching for the training and a character for everything around it. They read the same Apple Health data and do entirely unrelated things with it.