Is this waterproof head-gear the ideal solution for tracking your open water swims?.. It’s also pretty clever in the pool..

There are plenty of gadgets available to keep track of your swims, mostly wrist-worn fitness trackers and sports watches. The thing is, checking your wrist for waypoints and swim metrics isn’t ideal during mid swim as it interrupts your stroke. Also, the water messes with the GPS signal when your wrist is submerged.

The Platysens Marlin could be the solution. Firstly, what makes the Marlin different from most swim trackers is that it’s worn on your nut rather than around your wrist. There are other head-based swim trackers, such as XMetrics, but that doesn’t have a built-in GPS like the Marlin. Strapping tech to your head makes more sense than the wrist, as it doesn’t interrupt your stroke and minimizes drag.

There are two versions; the Marlin which features GPS for tracking open water swims; and the Marlin-P (P stands for pool) which is designed for pool swims and has no GPS. The GPS is the only difference between the two versions.


The Platysens Marlin uses bone conduction technology (BCT) to provide real-time audio feedback about your swimming metrics and GPS data. Bone conduction audio transmits sound through bones in your skull to the inner ear. BCT is used in the military and has been gaining the attention of cyclists as a way of listening to music without blocking the ears, thus being safer on the road. The Platysens Marlin is the first device to use BCT audio in a dedicated GPS swim tracker.

The Marlin can be set to open water mode or pool mode using a combination of GPS and a 6-axis motion sensor.

Open Water

Open water features include: speed, time splits from fixed distance, navigation and warnings if you’re off course, distance from waypoints, total swim distance and duration.

In the Pool

Pool features include: number of laps, lap time, stroke rate, and total swim duration.

Included with the Marlin package will be a session trainer which relays your swim programs via audio feedback. As well as receiving your data in real-time, you can review your swims on dry land by syncing Marlin via Bluetooth to your smartphone.

Battery Life

Platysens say the GPS-enabled Marlin will last up to 5 hours on a full charge. The non-GPS Marlin-P will last up to 10 hours. To help with the device’s waterproofing, the battery is charged through the headphone jack.


The swim tracking headgear has an IPX8 waterproof rating, which means it’s safe at 1.5 meters below the surface for 30 minutes, hence, it’s not suitable for diving.


Compatible with iOS and Android devices which support Bluetooth Smart.

Price and Release Date.

The retail price will be $150 USD for the GPS-enabled Marlin, and $120 for the Marlin-P. Discounted prices starting at $80 (Marlin) and $62 (Marlin-P) are available now over at Kickstarter.

Kickstarter backers should start receiving orders in January 2017.