A strength tracker that works with no signal in the gym.

Log sets, reps, and rest on your phone, offline. Everything reconciles to your own account when the connection comes back. Food, sleep, and heart data from Apple Health land in the same daily picture.

See the app Read the API docs

Exercise list showing estimated one-rep max per lift — Estimated 1RM per lift, with personal bests marked.

Squat detail showing estimated 1RM trending up over eight sessions — Eight weeks of squat, and every session behind the trend.

Workout history list — Sessions as they were logged, set by set.

Daily energy balance: calories in, calories out, the day's macros, and 7- and 30-day averages — Calories in against basal rate and Apple Health workouts, averaged over the last 7 and 30 days.

Nutrition log showing meals with per-entry macros and a daily total — Every meal with its macros, totalled per day.

Sleep history showing stage breakdown and sleep efficiency per night — Sleep stages and efficiency, imported from Apple Health.

Counted by tapping

A partner taps the bottom and top of each rep, or you log manually with a rest timer running. No fiddling with a keyboard mid-set.

Progression that means something

Estimated one-rep max, top set, and volume tracked per lift, so a good week is visible as a number rather than a feeling.

One daily picture

Food and supplements weighed against Apple Health workouts, sleep stages, resting heart rate, and your basal metabolic rate.

Offline first, by design

The phone is the source of truth. Writes queue in an outbox and reconcile through a delta sync. Gyms have bad reception.

Under it

Bidirectional delta sync: an on-device outbox, server cursors, and tombstones, so two devices converge without losing a set.
Row-level security in Postgres: every user-owned table carries a policy that fails closed, enforced by the database rather than by application code remembering to filter.
An agent API: scoped API keys and OAuth 2.1 with PKCE, plus an MCP server, so an assistant can log a meal on your behalf.
Audited and undoable: every write an agent makes is recorded, attributed, and reversible from your account.

Read the API docs

Early access

UA Strength is in a limited pilot with Five College students: Amherst, Hampshire, Mount Holyoke, Smith, and UMass Amherst. Accounts are created with a college email address at one of those schools.