Zai is a fitness app for Indian bodies and Indian lives. Inside, an AI coach named Sarathi rebuilds your day every morning — around your sleep, your sore knees, and the rajma chawal you had for lunch.
Most fitness apps hand you a plan and walk away. They don’t ask what you ate, how you slept, or whether your knees agree with today’s squats. They treat Tuesday’s you the same as Sunday’s you.
I’m built differently. Every morning I read what changed overnight — your sleep, your soreness, the meal you logged at 11 p.m. Then I redraw your day around it. The same way a good coach in a real gym would, if a real gym sat in your phone.
You’ll talk to me the way you’d talk to a friend. “Skipped dinner, head’s foggy.” “Snap of my dal, log it.” I’ll handle the rest — the sets, the macros, the will-this-aggravate-my-back math.
This issue is the brief. Read it, and if it sounds like the coach you’ve been waiting for, the back page tells you how to come along.
Zai is one app, but five quiet acts of attention. Each one is small on its own. Together they’re the difference between a plan and a coach.
Sarathi lives in a chat thread, not a settings menu. Tell it you’re sore, ask why today’s sets dropped, send a photo of your fridge at 9 p.m. — it answers like a human coach would.
No streaks to break. No empty motivational quotes. Just conversation that turns into a plan.
Slept four hours? Sarathi pulls back the volume. Hit your bench PR yesterday? It bumps the next session up. The plan adapts each morning — to sleep, soreness, mood, schedule, and what you ate.
You see the change, you see the reason, you press play.
Indian meals don’t fit barcode databases. Sarathi understands rajma chawal, thali, “two rotis with sabzi”. Speak it or photograph it, in any of three languages, and it logs the whole meal — portions and all.
That’s the morning check-in. Energy, sleep, soreness. From those three taps, Sarathi rebuilds your day — the workout, the protein target, the mood it speaks to you in.
It’s the smallest ritual in the app, and the one that does the most work.
Onboarding takes about ninety seconds. By the time it’s done, Sarathi has drafted the next two months — knowing your goal, your gym, your schedule, the lifts you’ve measured before, and what you actually like to eat.
Sarathi is the brain of Zai. It reads every signal — your sleep last night, the lift you logged this morning, the meal you typed in last Thursday — and turns it into a single plan that’s already up to date when you open the app.
You don’t manage it. You just talk to it.
Not a workflow. A small daily rhythm. Most of it Sarathi does for you in the background.
Leave us your email. When Zai opens up, you’ll be among the first few hundred to meet Sarathi. No spam. No drip campaigns. One quiet note when it’s your turn.