Your watch and oswim — what arrives, brand by brand

iPhone and Apple Watch

The oswim app reads your swims from Health, with your consent and read-only. Your whole history arrives at the first sync, then every new swim.

What arrives

With an Apple Watch: date and time, duration, distance, split times, heart rate (average, maximum, curve, and the three minutes after the swim), calories, effort (iOS 18 and later) and the stroke count per stroke style. In a pool, the pool length, each length with its stroke, and SWOLF. In open water, the GPS route. Water temperature, if your watch measures it (Apple Watch Ultra, Series 10 or 11).

What does not arrive

The stroke count length by length: only the total per stroke style arrives. In open water, no lengths and no SWOLF: the watch does not record them.

Other watches, through Health

oswim reads any swim written to Health, whichever app put it there: it arrives with what that app wrote, and with its route only if the swim is marked “open water” there.

• Garmin: a swim Garmin Connect writes to Health arrives with what it holds, depending on the model. The watch's own file stays the most complete.
• Suunto: a swim the Suunto app writes to Health arrives with what it holds, depending on the model. The watch's own file stays the most complete.
• COROS: a swim the COROS app writes to Health arrives with what it holds, depending on the model. The watch's own file stays the most complete.
• Polar: a swim Polar Flow writes to Health arrives with what it holds, depending on the model.
• Withings: of a swim, the watch only measures the duration and calories; at best, that is what arrives.
• Huawei: Huawei Health writes your workouts to Health; a swim arrives there with what it holds, depending on the model.

Android

The oswim app reads your swims from Health Connect, with your consent and read-only. Health Connect carries neither water temperature, nor stroke count, nor SWOLF, and effort is not read: those boxes stay empty, whatever the watch.

What arrives

What the brand's app wrote there: date and time, duration, distance, heart rate (average, maximum, curve) and calories. In a pool, the lengths and their stroke. In open water, the route, if the brand's app writes it and you allow oswim to read it — Health Connect may ask for that permission swim by swim.

What does not arrive

Water temperature, stroke count, SWOLF, effort and split times.

Brand by brand

• Samsung (Galaxy Watch): Samsung Health writes the workout with distance, heart rate and calories, but not the route.
• Pixel Watch and Fitbit: in open water, the watch only records duration and heart rate — no distance, no route. In a pool, it adds lengths, distance and calories.
• Withings: of a swim, the watch only measures the duration and calories; at best, that is what arrives.
• Garmin: Garmin Connect writes measurements to Health Connect (calories, distance, heart rate…) but no workout, so oswim finds no swim there. Use the watch's file instead.
• Polar: Polar Flow writes its workouts to Health Connect, route included according to Polar; a swim arrives with what it holds.
• Suunto: what the Suunto app writes to Health Connect is not documented by the brand. The watch's own file stays the most complete.
• COROS: its app only writes part of its data to Health Connect, according to its users; for a swim, it is not documented by the brand. The watch's own file stays the most complete.
• Huawei: Huawei Health does not write to Health Connect. On Android, that leaves entering the swim by hand, or a file if you have one.

File

On the website, with an account: up to 10 files at once, 200 MB in total.

• Apple Health export (.zip): date and time, duration, distance, average and maximum heart rate, calories, pool length and SWOLF, water temperature if the watch measures it, and the route of open-water swims. No per-length detail, no heart-rate curve, no split times.
• Garmin export (.zip): the .zip from “Export Original” holds the watch's FIT file; it is read as a FIT.
• FIT (watch or HealthFit): the most complete format. Date and time, duration, distance, heart rate (average, maximum, curve), calories and split times; in a pool, each length with its stroke and stroke count, and SWOLF; in open water, the route; the temperature the watch recorded, if it has a sensor. No effort.
• GPX (route only): the track and its times. Distance is measured along the track and duration runs from the first to the last point, stops included. No heart rate, no calories, no lengths.

Where to find your files

• Apple Watch — free: on the iPhone, Health app → your profile picture → “Export All Health Data”, then import the .zip as is. Your whole history arrives at once.
• Apple Watch — per-length detail: the HealthFit app (one-time purchase) exports each swim as .fit, the richest format.
• Garmin: on Garmin Connect (desktop), open an activity → “Export Original”, and import the .zip as is.

By hand

Write a swim down by hand: the date, the duration, and it is saved. Everything else is optional.

You can add the distance, the beach (to find the sea as it was at that hour), the end time, the pool length, the water temperature, average and maximum heart rate, calories, SWOLF, the stroke count and stroke, perceived effort, your equipment and your notes, visible to you alone. Without a distance, the swim keeps its duration alone: no pace is invented.

If your watch later sends the same swim, oswim offers to keep the watch's, carrying over your note, your effort and your equipment.

Strava

No direct import from Strava today: the way in is your watch's file, which the Strava website also lets you download, activity by activity.