Casio Pro Trek Smart WSD-F20 review

A rugged Android smartwatch for adventure seekers

TechRadar Verdict

If you absolutely must have an outdoor watch that’s also a ‘proper’ smartwatch then the second-gen Wear OS-toting Casio Pro Trek Smart is one of only a few options you have to choose from. It’s better than the first generation and there are some clever things to love but overall it’s a disappointment. For our money there are too many design flaws to make it worth the hefty price tag.


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    Color offline maps

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    Power-saving monochrome screen

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    Low-power GPS


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    Bulky design

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    Terrible charging cable

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    Poor screen visibility

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The rugged and chunky Pro Trek Smart WSD-F20 is Casio’s second attempt at an adventure-loving Android smartwatch for people who like to hike the hills, paddle up stream and generally get off the grid.

A replacement for the Casio Smart Outdoor Watch WSD-F10, the WSD-F20 looks almost identical to its predecessor, although it’s slightly thinner. The major headline upgrade here, though, is the inclusion of built-in GPS, so now you can take on the great outdoors without your phone. That’s an improvement but something you’d really have expected in the first generation.

Even though at £450/$500 (around AU$650) it’s got a price tag that puts it up there with the top-end timepieces in the big smartwatch line-up, the Casio Pro Trek Smart shouldn’t really be compared to mainstream everyday devices like the Apple Watch 3 or those Android Wear watches such as the LG Watch Sport.

This is a niche device that will appeal only to those who like to get a bit of dirt under their nails outdoors and is more at home up against the likes of the Nixon Mission, and non-Android sport watches from the likes of Suunto and Garmin.

Fortunately for Casio, there aren’t too many true smartwatch alternatives that cater for the outdoors and that makes the Trek’s combination of Wear OS smart features plus tracking for hiking, canoeing, snow sports, cycling, skiing and, um, fishing, a consideration. However, you’ll also want to seriously look at regular outdoor watches that come with some smart features too.

Design and screen

  • GPS connectivity but no heart rate or NFC
  • Supports both Bluetooth and Wi-Fi
  • Compatible with Android 4.3 or later and iOS 9.0 or later

The Casio Pro Trek Smart is unapologetically an outdoor watch. There’s no subtlety here. It’s a hulking great thing for a start, and measuring in at 61.7 x 56.4 x 15.7mm it’s quite noticeably bulkier than a rival Suunto Traverse or the Garmin Fenix 5X.

Its chunky faux metal finish plastic casing, paired with an oversized black protective bezel – complete with silver metal stud screws – makes the whole thing look a bit like a watch that’s wearing Iron Man’s armor.

It screams rugged from about 100 feet away and as outdoor watches go, it’s not entirely unattractive. But unless you’re Bear Grylls going to a big meeting, you probably won’t want to wear this with your suit to work, not least because it won’t fit under the cuff of your shirt but also because it’s heft makes it quite hard to type.

Inside the big bezel sits a 1.32-inch dual-layer touchscreen display that's nice and responsive with fast, smooth transitions between screens and features. It can also be cleverly flicked between color and monochrome for power saving. (It does this automatically once the power gets low).

We loved this feature for its battery conservation smarts but that’s about all we like about this screen. Even with five levels of adjustable screen brightness, we found the slightest bit of light on the screen made it largely impossible to read in all kinds of daylight conditions which is a huge problem for an outdoor watch.

At 92g it’s heavier than something like the Suunto Traverse (80g) and the Garmin Fenix 5 (82g) too, and the version we tested, with the inflexible and rigid standard watch band, was far from a comfortable fit. Harder wearing maybe, but for a watch designed to be worn for long periods while you’re trekking or taking on long adventures, it really came up short.

In terms of physical controls, the Casio Pro Trek Smart WSD-F20 features three big side buttons on the right of the watch – Tool, Power and App – which are all easy to find on the move if a little soft and unresponsive on the press.

The Power button, which also returns you to the home screen, is neatly protected by two button guards to stop any accidental shutdown. Meanwhile the Tool and App buttons can be assigned to different functions, but initially Tool launches the Compass and the App button loads up the maps.

Under the hulking great hood there’s a host of sensors including a pressure sensor for air pressure and altitude, an accelerometer, gyrometer and magnetic compass.

As you’d expect from an adventure watch, durability is key, and the Pro Trek Smart comes with MIL-STD-810G standard military-grade levels of protection and it certainly feels like it’ll take more than a knock or two. It’s water-resistant to 50 meters, so swimming, sweat and rain are taken care of, however diving and water sports like windsurfing are not recommended by Casio.

One surprising inclusion that we’d actually love to see in other sports watches is a built-in mic that lets you take notes and tag them to your current location. Ideal for capturing those eureka moments of inspiration you often unlock when you’re sucking in lungs full of fresh mountain air.

Color-wise, the Pro Trek Smart comes in straight-up black, black and green highlights, black and white, and black and orange (our favorite).