Garmin Instinct 3 Tactical Solar 45mm smartwatch

The Garmin Instinct 3 Tactical Solar 45mm Smartwatch is high quality. If you’re more interested in your watch being able to do stuff for a long time than being particularly pretty or flash, then it’s one for the shortlist.

The Instinct 3 Solar features a 45mm fibre-reinforced polymer case with a metal-reinforced bezel and it’s waterproof to 100m. There are five control buttons that give you access to all the functions; there’s no touchscreen here.

You get a fairly standard silicone strap, and the rear face houses the heart rate sensor and the charging port. It’s chunky without being huge, and not the prettiest watch you’ll find, although Garmin is obviously going for a rugged aesthetic, which it has pretty much nailed.

Because the interface is all button-based, it takes a bit of time to learn where everything is, and it’s certainly not as intuitive as a touchscreen watch. To change an alarm, for instance, you’re about four layers of menu deep before you’re actually picking a time. Like anything else, though, you’ll get used to it, and there’s a lot of functionality built in.

The tactical edition of this watch, which I’m testing, has a bunch of features that I’m not going to need, and neither are you, and neither is anyone short of a real-life tactical unit.

There’s an Applied Ballistics solver which gives you access to aiming solutions for long-range shooting in the field, and a Jumpmaster mode to calculate high-altitude release points for your incursions in enemy territory. If you get caught, the kill switch wipes the device of all user memory so you won’t give away valuable positioning data. There’s a screen setting for night-vision goggles too.

Anyone need any of those? Me neither.

So: why review it here then? Well, Garmin sent us one, and in addition to all of that there’s a bunch of genuinely useful stuff here, that you also get on the non-tactical version – if I were buying this watch then the standard Instinct 3 Solar, at £80 less, would definitely be my pick.

The Instinct 3 Solar has a great battery life, and a solar panel to top it up on sunny rides. It’s got multi-band GPS and a barometer, and you can track a range of activities on it, and it’ll sync them to the Garmin Connect app on your phone. Things can flow the other way too: you can choose which apps can notify you, so you can stay on top of stuff without having to get your phone out of your pocket. You get Garmin Coach monitoring your condition, and access to 1,600 different workouts. The heart rate monitor can also measure your blood oxygenation and your heart rate variability. There’s a proper torch in the bezel. You can even use Garmin Pay through the watch to get your mid-ride coffee and cake.

Garmin Instinct 3 Tactical Solar: Battery life

This watch has a low-power single-colour LCD display. It has a larger main section and a circular detail top right, and it’s nice and clear and easy to read, day and night. There’s a backlight which is turned on and off by the top left button, and you can set the brightness to suit your needs.

An LCD draws minimal power, so even before we start talking about the fact that it charges via a solar panel, the battery life is prodigious. When I first charged it and put it on, the watch suggested it’d be the best part of a month before I’d need to take it off again. That was maybe optimistic: after 12 days or so it was down to under 50 per cent, at which point it was a nice sunny day, so I left it out for a few hours in the full sun to see if the solar charging is effective. It is: I added about 30 per cent of charge to the battery, which would equate to at least another week of use.

If you spent a lot of time outdoors and the weather was nice, it’s entirely possible you could wear this watch all summer without having to charge it once: on a long (7hr) bike ride in mostly sunny conditions, the Instinct 3 got home with two more days of life than when I set off. That’s not with it in some low-power mode either: the watch was on, with Bluetooth enabled, and it was connected to my phone. I tracked a few activities and used the torch a bunch of times too. It’s not like I was trying to eke out the juice for as long as I could. In normal use, this watch lasts for absolutely ages.

So far I’ve had to use the proprietary charge cable maybe once a month. Beat that, other smart watches. Even the Honor GS Pro I reviewed a while ago – which has excellent battery life for an AMOLED smartwatch – didn’t last this long. I’m not a fan of smart watches that you have to remember to charge on a regular basis, so this is a big plus for me.

The trade-off is that the screen isn’t as nice to look at and the lack of a touchscreen makes menu navigation a bit trickier. There are other smartwatches out there that have good battery life and also pretty screens: I’m currently reviewing the Huawei GT6 Pro as well, and that’ll go a couple of weeks between charges.

Garmin Instinct 3 Tactical Solar: Recording activities and following routes

One of the main things you might want to do with your smartwatch is use it to record your activities, especially if you’re more of a multisport athlete. The Garmin Instinct 3 Tactical Solar comes with presets for running, riding, pool swimming, gym work, skiing and snowboarding in the menu and there are literally hundreds of other activity types built in – everything from snowmobiling to golf.

To log activity, you need to pair your watch with the Garmin Connect app on your smartphone, and by doing that you also get to play about with some of the default menus, so you can replace the stuff you’re not going to use with stuff that you are. This is especially useful for the activity shortcuts, and the controls wheel that you access by holding down the top left button. You can also change the watch face, add a payment card, set up live tracking and incident detection, set up incoming call and message responses, and go through the deeper settings. There’s a ‘find device’ function on the app if you’ve put your watch down somewhere, but if you’re like me you’ll be using the ‘find phone’ function on the watch a good deal more regularly – at least once a day in my case.

There are plenty of other aspects of the Garmin Connect app too. A fully featured nutrition planning and calorie management plan is a paid extra, but you can set up a bike training plan based on your goals for free, so if you’re working towards a specific goal you can lock in some structured training along the way, and complete the workouts either indoors or outdoors.

You can plan your own routes using the app too. Connect will spit out an automatic route based on a start point, compass direction and distance. This works decently enough for road rides but I found that for gravel it tended to route me down stuff you shouldn’t really ride, so it wasn’t great for that. The custom route option is waypoint-based like komoot or Strava, and is pretty good: you can still head down footpaths if you want, though.

Once you save a route, you can sync it to the watch and then you’re ready to go. There’s no mapping as such on the watch: you get a breadcrumb trail of the route, and you can set that to auto-zoom in and out depending on your speed, and also to rotate to your direction of travel. You get turn by turn directions on the watch – it’ll vibrate to let you know – and if you’re synced to your phone you can also get audio cues through your headphones. I found that the ‘upcoming turn’ instructions were useful, but the actual turn cues were too late: I’d already started the turn by the time the app told me to. If you go off-route then you don’t get directions back to it, but you can see where the route is and muddle through accordingly.

I found the GPS to be fairly accurate, although it’s not as good as a dedicated bar-mounted GPS unit. The line tended to roam a bit where there was significant cover, but never to the extent it was a problem. Heart rate sensing is a bit more patchy: you have to get the strap pretty tight for it to work reliably, and even then it’s quite dependent on position on your arm. This isn’t really any different to other watches I’ve tried. You can see from the HR plot from this ride that it wasn’t reliable for the first section until I tweaked it, but after that it was fine. Elevation and speed data are GPS-reliant, and so are pretty good.

The Garmin ecosystem has a lot of other fitness functionality too. Of course you get step tracking, and a daily target that moves about by default depending on your level of activity. You can track your VO2 Max (as estimated by the app) and also see how you’re acclimatising to heat or altitude. There’s a health snapshot function, and a daily morning report that updates you on your sleep and other metrics. You can log hydration, and track intensity minutes and stress levels. If you’re keen on data, then there’s a lot of data on tap.

Garmin Instinct 3 Tactical Solar: Torch

This may not seem like a big deal, but the Garmin Instinct 3 has a torch. If you’ve got a smartwatch, it likely has a torch setting, where the screen lights up, and that’s good for finding your earplugs in the night if your significant other starts snoring. But this watch has an actual proper two-LED torch, at the front, which you activate by double-clicking one of the buttons. You can adjust the brightness, and also set it to green light which doesn’t mess quite as much with your night vision if it’s really dark.

I’ve found the torch enormously useful. Okay, your smartphone has a torch, but you have to get your smartphone out, and hold it. Your watch is just there, ready to go for when you’re looking for stuff in the dark corner of a shed, or trying to fix your bike on an unlit lane. You’re still a bit restricted by what you can do with the arm your watch is on, and it’s not as versatile as a headtorch, but I’ve found myself using it as much as any of the features of the watch. In an emergency – and it would have to be an emergency – you could rig it up to your bars and use it as a bike light if all else fails. You wouldn’t be going quickly, but you would be able to keep moving. It’d be better than that time my light broke and I had to navigate the pitch black lanes by shining my GPS screen at the road, anyway…

Garmin Instinct 3 Tactical Solar: Value and overall

At £429.99 the Instinct 3 Tactical Solar isn’t cheap, but it’s not in the ballpark of devices like the Apple Watch Ultra 3 or Garmin Forerunner 970 either. Realistically, unless you’re in the parachute regiment you can get all the functionality you need on the non-tactical version of the watch, which is £80 less, so my value judgements are mostly based on that.

For the same money you could bag yourself a Coros Pace Pro GPS Sport Watch which has excellent functionality and an AMOLED screen that allows you to use full mapping for navigation. Battery life is fine, but we’re talking days rather than weeks.

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The big draw of the Instinct 3 Solar is the battery life: I’ve never used a smart watch that needed charging less. The torch is surprisingly useful, and the smartwatch functionality is good: it’s not as intuitive as some thanks to the button-based interface but it’s very usable, and if you’re recording more than just bike rides – or you like access to a lot of data – then it’s well worth a look.