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The tech-boosted G-Shock GA-B2100 watch is a great buy

It can initially be quite hard to grasp why the little Casio G-Shock GA-B2100 is such a brilliant watch. After all, it’s cheap, it’s not a sci-fi-influenced limited edition, and on the technology side, it’s not as comprehensively specced as a fitness-orientated G-Shock, let alone an Apple Watch.

Yet it’s one of my favorite G-Shock watches of recent times, and a great buy. Here’s why.

Why is it popular?

The original G-Shock GA-2100 (note the lack of the B in its name) came out in 2019 and was an instant hit. The $99 price point was just right, the analog/digital look is pure G-Shock, and it was available in various colors so it appealed to the many people who buy G-Shock watches as fashion accessories. The passing (if you squint very hard) resemblance to the Audemars Piguet’s octagonal Royal Oak luxury watch helped build its legend online too.

The yellow G-Shock GA-B2100 seen from above.
Andy Boxall/Digital Trends

More colors, a metal-cased version, and a limited edition of the GA-2100 made with Rubik’s Cube have been released since then, but the GA-B2100 is the first overhaul of the model that adds more features, and the choice is spot-on. The GA-B2100 comes equipped with a Bluetooth connection and Casio’s Tough Solar charging, making the GA-B2100 one of the highest-spec entry-level G-Shock watches available.

Despite these two significant upgrades little else about the GA-B2100 has changed compared to the simple GA-2100. It’s still the thinnest G-Shock around at about 11mm so it remains incredibly wearable, the weight is minimal at 52 grams, and there are multiple color options. Adding new tech has affected the price, but not by much, as the GA-B2100 starts at $150 (129 British pounds), and for that, it’s an absolute steal.

Bluetooth connection

Although some Casio G-Shock watches include more fitness tracking features today, such as the GBD-200, the GA-B2100 is a simpler affair. The Bluetooth connection syncs to your phone to set the local time, and in the app you can adjust features like the alarm, timer, and world time. It’s easier, faster, and more natural to use the app than to learn the process of doing so on the watch itself.

Side view of the G-Shock GA-B2100 on a man's wrist.
Andy Boxall/Digital Trends

Casio has recently released a new app called Casio Watches, which replaces its old G-Shock Connected app, and I took the opportunity to try it out for the first time when using the GA-B2100. The app’s look, with black text on a white screen, is clean and easy to read, and I like the way you can choose your exact watch to show in the app, rather than the less personalized generic option in the old app.

Choose a feature like setting the world time and a map shows alongside it for some extra visual interest, while the other features are all simply laid out and very quick to use. It’s certainly faster, less flashy, and more feature-focused than the old Connected app.

However, the main Home page is just a collection of ads for G-Shock and a repeat of its Instagram feed, serving no purpose. I’d rather see my watch collection highlighted when I open the app. That said, the Bluetooth connection with the app has worked without a problem since that first try, and reconnecting the watch after it has automatically disconnected takes a single long-press of the Mode button. Superfluous home pages aside, it’s exactly what a companion app should be like.

Tough stuff

The GA-B2100 uses Casio’s Carbon Core Guard structure to protect the components inside from vibration and impact, and wraps a resin body and strap around it for additional toughness. It’s entirely shock-resistant and water-resistant to 200 meters, so you’re not going to break the watch without really trying hard.

I like the bright lume with its green tint on the hour and minute hands, and the way its bright white color makes the dial more legible when quickly glancing at the time. A piece of flat mineral glass covers the dial, and there are four buttons on the case and a screw-down stainless steel case back.

The Tough Solar charging is all that’s needed to power the watch and the Bluetooth connection, and it takes its energy from both sunlight (even when its cloudy) and fluorescent indoor lighting. Casio estimates it would last seven months without seeing any light at all after being fully charged for it to run out of charge, so you won’t have to worry much about the battery being depleted if you wear it regularly.

Press the Mode button to cycle through the features displayed on the digital LCD screen. It’s definitely not the biggest screen, but it does the job for checking the world time or your alarm settings, plus if you press the Light and Mode buttons at the same time, the hands automatically shift out of the way if they’re obscuring it. The analog complication shows the watch’s mode and if the Bluetooth feature is active, while in normal mode it points to an L, M, or H marker, which denotes the current level of solar charge, either low, medium, or high.

Wearing the GA-B2100

Forget any preconceptions about all G-Shock watches being big and bulky, the GA-B2100 is neither of these things. The sleek case is so easy to wear because of it, yet in the right color, it can still make a statement, particularly with summer on the way and the chance to wear short-sleeve tops. The 45mm case width sounds big, but I don’t think it dominates my 6.5-inch wrist, which you see in the photos, at all. The resin strap is flexible and comfortable, plus there’s absolutely loads of adjustment to get the fit just right.

Side view of the G-Shock GA-B2100 on a man's wrist.
Andy Boxall/Digital Trends

I’ve been wearing the blue GA-B2100-2A version and like the subtle matte finish, but have also seen a nonworking version of the really eye-catching yellow GA-B2100C-9A. The yellow version is very colorful, not only due to the case itself, but also because of the white hour markers, the yellow hand on the complication, the red Tough Solar logo, and the blue Bluetooth logo. You can also get a black, black/gray, and a green version of the GA-B2100, all of which recall the colors used on the original 80s G-Shock watches.

The octagonal 2100-series G-Shock kept everything simple, with a now-iconic shape, a clear functional dial, and easy wearability all for a low price. The GA-B2100 adds properly useful technology with solar charging and a reliable, useful Bluetooth connection for a modest amount more, without affecting the cool, fashionable simplicity of design at all. I think it’s great.

When can you get one? The GA-B2100 range will arrive in the U.S. around June, and it’ll be out in the U.K. at some point in May. All colors except the yellow model cost $150 or 129 pounds, with the tempting yellow watch at $160 or 139 pounds.

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