The fitness app built for iPhone Duo

What changes when iPhone Duo is unfolded

These layout facts were checked in the app code on 8 October 2026. They describe the unfolded phone. This page does not guess cover-screen behavior, hinge width or a screen-size number.

Unfolded, Home and Workouts show side by side in two columns. You can see the home surface and the workout surface at the same time instead of stacking them on one narrow column.

Landscape uses the full width. The layout does not leave black bars on the sides of the unfolded screen.

Layouts avoid the fold area, so controls and text are not parked on the hinge.

The tab bar moves to the side when the layout has room for it, instead of staying pinned to the bottom edge only.

Stats, the timer, Feed and Coach each have an adapted layout for the unfolded phone. The same features exist on a regular iPhone. The difference is how they use the wider canvas.

Gym, running and 40 activity types

The training model is the same app you use on iPhone. Log gym sets, reps and weight across 260+ exercises, each with a video demo. The source count on 8 October 2026 was 263 exercises. This site says 260+ so a new exercise does not immediately make the sentence false.

Runs and walks record a GPS route on the iPhone, including in the background, with time, distance and pace. There are 40 activity types: 8 strength, 14 cardio or wellness, 14 sports and 4 outdoor. Fourteen of those types are sports. Football, basketball, tennis, cycling, swimming, HIIT and yoga are among the activity types.

On iPhone alone you also get the rest timer, step counting, a free AI calorie estimate, and a readiness score from 0 to 100%. Apple Health sync reads steps, energy, distance and outside workouts, and it saves workouts. Live Activities and Dynamic Island show the timer, the rest countdown and a Complete set button.

The AI coach is part of the optional GOAT Plus subscription. It is not a Watch feature and it is not required to log a workout. The app does not offer Siri or Shortcuts support.

Apple Watch stays optional

You can train on iPhone Duo with no Watch paired. Without a Watch, effort is a 1–10 rating you enter. Heart rate is not estimated from that rating.

From the wrist you can start any activity, start a routine and check off sets, or start a Combo of up to 4 activities chained together. Live on the Watch, every workout shows heart rate, 5 heart-rate zones with time in each zone, average heart rate, and active and total calories. Running adds distance, pace, cadence, power, stride length, ground contact time and vertical oscillation. Walking and hiking add elevation gain and loss and VO2 max. Cycling adds speed, cadence, power, FTP and elevation. Pool or open-water swimming adds distance, pace per 100, laps, strokes, stroke style, SWOLF and stroke rate. Those stats sync live to your iPhone about every 2 seconds, in a Live Watch banner and on the Live Activity and Dynamic Island, which show BPM and the zone bar. Watch GPS points are added to the iPhone route map. Pause, resume, lap, end and discard work from either device. Afterward, zone time, average and max heart rate, calories, running form, cycling power and speed, and swim SWOLF, stroke breakdown and lap splits are saved to Apple Health.

Free download, GOAT Plus optional

Free download, with an optional GOAT Plus subscription. This page does not publish a price.

Logging workouts and routines, and the AI calorie estimate, are free. GOAT Plus includes the AI coach and chat, one-tap routine generation, weekly plans, muscle recovery, themes, extra widgets and full history.

The app also includes a social feed with follows, likes, comments and stories, a muscle heatmap, achievements, an AI nutrition check-in, weekly and monthly summaries, and Memories, which are photo collages with route stickers. Five widgets ship with the app: Live Activity, calories, step goal, streak and muscle recovery. The interface is localized in 17 languages.

Requirements: iOS 26 or later, iPhone only. There is no iPad app and no Android app. iPhone Duo uses that same iPhone app, with the unfolded layouts above.

Frequently asked questions