Short Version
Swimcast is built for MP3 swim headphones and waterproof audio players that appear as writable storage in the iOS Files folder picker. If your swim headphones can be connected to your iPhone and selected as a folder, Swimcast can copy numbered MP3 podcast episodes into that folder.
Headphones People Commonly Search For
Swimcast is designed around the same file-based workflow swimmers use with devices such as:
- Shokz OpenSwim
- Shokz OpenSwim Pro in MP3 mode
- AfterShokz Xtrainerz
- H2O Audio TRI, TRI 2, and TRI PRO-style MP3 swim players
- FINIS Duo
- Sony Walkman NW-WS410 and NW-WS620-style waterproof MP3 players, when their storage is visible to iOS
- Other MP3 swim headphones that expose a writable audio folder
What Matters For Compatibility
The brand name is less important than the storage behavior. Swimcast needs three things:
- The device connects to your iPhone over USB, usually through USB-C, an adapter, a hub, or the device’s charging cable.
- iOS can show the device or its audio folder in the Files folder picker.
- The device can play standard MP3 files after syncing.
Bluetooth does not work underwater, so Swimcast focuses on MP3 mode and file syncing instead of underwater streaming.
Device Notes
Shokz OpenSwim
Shokz OpenSwim appears as a storage device when it is connected through its USB charging cradle. Choose the OpenSwim drive or audio folder in the iOS folder picker, then Swimcast writes numbered podcast MP3 files in the playback order you selected.
Shokz OpenSwim Pro
Shokz OpenSwim Pro supports MP3 mode for underwater playback. Connect it with its magnetic USB cable, choose the SWIM PRO drive or your MP3 folder in Files, sync episodes, then switch OpenSwim Pro to MP3 mode before swimming.
AfterShokz Xtrainerz
AfterShokz Xtrainerz uses a similar storage workflow to OpenSwim. Put the headphones in the USB cradle, connect them to your iPhone through the right adapter or hub, and choose the mounted Xtrainerz storage folder when iOS shows it.
H2O Audio
H2O Audio players work with Swimcast when iOS can see their storage. Choose the folder where you normally put MP3 swim audio, then Swimcast replaces visible files in that folder with your selected podcast episodes.
FINIS Duo
FINIS Duo works when its mounted player storage is visible through the iOS folder picker. Choose the audio folder that stores files for playback.
Sony Walkman Waterproof MP3 Players
Some Sony Walkman waterproof MP3 players, including NW-WS410 and NW-WS620-style devices, use file transfer workflows. Swimcast can work with Sony-style waterproof MP3 players when iOS exposes their storage as a writable folder and the device can play the synced MP3 files.
Not Affiliated
Swimcast is independent and is not affiliated with, sponsored by, or endorsed by Shokz, H2O Audio, FINIS, Sony, or any other headphone maker. Product names are used only to describe compatibility.