● For iPhone and Apple Watch
The promise: no account, no ads, no subscriptions.
A workout log that lives on your devices and works fully offline. Exportable any time. Yours, forever.
Goal one
Every set is prefilled from the last time you did that lift. A normal day is lift, lock in, rest: one tap commits the set and starts the rest timer. The weight lights up when you beat last session, and PR badges land on the set that earned them.
Two kinds of training run first-class here: a lifting program and a running plan. Both are the same shape: a plan, a cursor, and the next day waiting when you open the app. Everything else gets logged.
Workout A, Workout B, the circuit you never write down. Saved once, started in one tap, every set prefilled from last time.
Periodized multi-day plans: percent waves and rep targets, week by week. When a cycle ends Delta asks for new top weights. You decide, every time.
A walk-to-run build, a twenty-week half. Import it from a spreadsheet and Delta walks it day by day. Run and walk timers live on your wrist.
Set by set on your wrist with live heart rate, and supersets alternate on their own. Lock in from either device.
"Press getting challenging." Jot it after a set and it is there on the card next time, dated. Every one you write is kept and readable. Delta never interprets any of them. A notebook has margins.
GPS runs with routes and heart-rate zones. Bluetooth machines stream straight into the log. None of it pretends to be a plan.
On the wrist
Start a program and the watch takes it from there: the set you are on, the weight, the target, live heart rate, and the rest timer. Turn the crown when you got more (or fewer) reps than planned, lock in, keep lifting. The phone stays in sync either way, and if life interrupts, pause from the wrist.
The same is true of a run, and it is the reason this app is native at all. The wrist holds the whole prescribed workout, not a reference to one: it knows the run/walk switches, taps you through them, counts a distance leg down in miles, and lets you skip a warm-up you already did. Twelve miles, nothing in your pocket. Your phone finds out when you get home.
The differentiator
Plateau detection, readiness signals, training cadence: every insight is a fact derived from your log, stated with its evidence. Each one stays silent until there is enough data to be honest, and none of them will ever tell you what to do.
Your data
Import your training history from other lifting apps, major export formats directly, or fill Delta's blank template in any spreadsheet. Either way, your old PRs are first-class citizens in minutes. Export everything as CSV whenever you like. The file is yours to keep, graph, or leave in a drawer.
| date | exercise | weight_lb | reps | warmup | minutes | distance_mi | |
|---|---|---|---|---|---|---|---|
| 1 | 2026-01-05 | Back Squat | 135 | 5 | yes | ||
| 2 | 2026-01-05 | Back Squat | 225 | 5 | |||
| 3 | 2026-01-07 | Run | 32 | 3.1 |
The filter
Delta has no account system, no analytics, no tracking, and no servers. Your log syncs through your private iCloud; the developer cannot read it. This is not a policy that could change. It is an architecture. Read the whole policy; it is short, because there is very little to say.