TautFit
iPhone & Apple Watch

A lab instrument for your training.

Type what you did the way you'd say it out loud. TautFit resolves it, compares it against every session you've logged, and tells you what to train next — with the receipts, not a guess.

Strength and conditioning both first class. No feed, no ads, no streak guilt.

Three seconds to log. Years of memory behind it.

Everything runs on your phone first. It works in airplane mode, in a basement gym, on a dead connection.

01

Write it however you say it

“incline db press 27.5 3x10, last set tough” lands as three structured sets. Numbers are parsed by a strict grammar — never by a language model, because a hallucinated weight is worse than no weight. Your raw text is always kept.

02

It learns your vocabulary

Call it “that pec squeeze machine” once and TautFit remembers the mapping forever. Phrases you've used before resolve instantly and offline. You can see every alias it has learned, and correct any of them.

03

Every set gets compared

Ghost sets show last session's numbers while you're logging. Personal records are detected mid-set. Estimated 1RM, volume per muscle group, pace trends and plateau detection are computed on device — instantly, and free.

Built for how people actually train.

Barbells and treadmills are the same kind of thing here: a session entry with its own metrics.

Strength and conditioning, unified

Lifting, cardio machines, distance work, HYROX-style stations, and mind-body sessions all live in one timeline. Cardio earns pace records the same way a squat earns a weight record.

A coach with reasons

Smart pick recommends your next session and always shows the arithmetic behind it. It routes around injury flags you've set, and it will tell you to take a Zone 2 day when your lifting load says so.

On your wrist

Log sets, feel the rest timer, and watch live heart rate from the Apple Watch app — including offline, with everything merging back when you're in range. Streaks show up as a complication.

Programs that progress

Seven templates over three progression rule types — linear, double progression, percentage waves — that read your actual history to set next session's targets instead of a static spreadsheet.

Apple Health, both directions

Completed gym sessions are written back so your rings stay honest. Watch and outdoor workouts import automatically, so a run you already tracked never needs logging twice.

Your history comes with you

Import years of CSV history from Strong or Hevy and the comparisons work from day one. Export the whole thing back out any time. Your data is yours — that's a feature, not a concession.

What TautFit deliberately isn't.

Every one of these was considered and cut. The app is better for their absence.

No social feedShare a PR card if you want to. There's nobody to follow.
No meal trackingA different problem, badly served by bolting it on here.
No daily streaksStreaks are weekly, because rest days are training.
No badge spamNo achievement exists that isn't a real training outcome.
No GPS trackingYour watch already does it well. TautFit imports it.
No ads, everThe subscription is the business model. That's the whole list.

The free tier is the app.

Almost everything TautFit does is arithmetic on your own data, which costs nothing to run — so it's free. The subscription starts exactly where the AI's running cost does, and nowhere earlier.

Free
$0
No account required to start
  • Unlimited logging and full history
  • Personal records, estimated 1RM, muscle balance, trends
  • Smart pick recommendations with their reasoning
  • All seven programs and progression targets
  • Apple Watch app, Live Activity, widgets
  • Apple Health import and write-back
  • CSV import and export
  • Free-form exercise resolution and 10 coach messages a week
The weekly coach quota resets every Monday.
Pro
$59.99
per year — or $9.99 monthly. 14-day free trial.
  • Unlimited coach chat, no weekly quota
  • Full program design built from your training history
  • Unlimited AI logging — free-form import and exercise matching never run out
  • Coach notes on every session, without spending quota
Cancel any time in your Apple Account settings. No lifetime tier — running the models costs money every month, and pretending otherwise would just mean shutting it off later.