The latest update to Garmin’s class-leading Fenix adventure watch adds something that could save your life: phone-free communications and emergency messaging on 4G or via satellite.The Guardian’s journalism is independent.We will earn a commission if you buy something through an affiliate link.Learn more.The Fenix 8 Pro takes the already fantastic Fenix 8 and adds in the new cellular tech, plus the option of a cutting-edge microLED screen in a special edition of the watch.

It is Garmin’s top model and designed to be the only tool you need to more-or-less go anywhere and track anything.That makes it an extremely pricey proposition starting at £1,030 (€1,200, $1,200, A$2,300) for the 47mm OLED version and stretching to a colossal £1,730 (€2,000/$2,000/A$3,399) for the 51mm version with microLED display – almost twice the price of the regular Fenix 8.You do get a lot of watch for your money with best-in-class workout, activity and adventure tracking.The full offline maps of the globe can automatically guide you back on to the trail if you get lost without a phone, and look great on the large, sharp and super-bright touchscreen.The Fenix 8 Pro only comes in 47mm or 51mm case sizes, not the smaller 43mm version Garmin offers in other models, so it is a big watch for big wrists.

But the 47mm OLED version as tested does have an extra day of smartwatch-use battery life even with the screen on all the time, lasting a solid eight to nine days between charges,Garmin has its own inReach LTE (4G) and satellite subscription service instead of relying on a watch plan linked to your phone provider, like other smartwatches,But unlike Apple or Google’s satellite-capable devices, emergency SOS messaging is not included for free,Instead, plans start at £7,99 or equivalent a month, which provides unlimited LTE text and voice messaging, calls and LiveTrack location sharing – so your friends or loved ones can keep an eye on you while out running, cycling or similar – plus emergency satellite SOS messaging.

Check-ins and texts over satellite are then charged on top, with more expensive plans including various allowances of satellite use, climbing to a £50 a month unlimited plan.The watch comes with a 30-day free trial so you can test out the service.Once you have got it set up, you simply head out the door without your phone and the watch will connect to LTE.You can not use it for streaming music or similar, but you can make and take calls, send texts and generally keep in touch with your family and friends.When you text someone, Garmin sends them an SMS from a random phone number, which they can reply to back to your watch.

If they install the Garmin Messenger app, you can then message back and forth via text or voice messages, and make voice calls.Your recipient does not need a Garmin account to use the Messenger app, just a phone number is sufficient to register for texts.Messaging on the watch works fine but typing out texts on the tiny on-screen keyboard is slow.It has a set of customisable canned responses you can send to speed things up.Voice messages and calls work OK, though as with most smartwatches, you’re not going to want to use it for extended conversations as the quality is not fantastic.

LiveTrack is the most useful feature.You can configure it to automatically send a link to chosen contacts every time you start an activity, so they can follow your real time location on a map.It’s great for following race progress, but it mostly serves as a tool for someone you trust to know your whereabouts in case something happens.It has generally worked well, though the real location has sometimes lagged when moving in and out of good LTE signal.All of these features are available on other Garmin watches if you carry your phone with you, but in the places where LTE does not reach, the satellite kicks in on the Fenix 8 Pro to send texts, location check-ins and emergency SOS.

A guide shows you how to find the line of sight to the satellite, which then sends and receives messages within about 10 to 30 seconds.It was surprisingly easy to use and could be a crucial lifeline, though it is important to note that satellite coverage is restricted to the US mainland, most of Canada, and most of Europe except for parts of Scandinavia above 65 degrees north.The watch is generally repairable with options available via the support site.The battery is rated to maintain at least 90% of its original capacity after two years of weekly charging.The watch does not contain any recycled materials.

Garmin offers recycling schemes on new purchases.The Fenix 8 Pro costs from £1,029.99 (€1,199.99/$1,199.99/A$2,299).

The optional Garmin inReach subscription plans cost begins from £7.99 (€9.99/$7.99/A$13.50).

The Fenix 8 Pro takes a fantastic adventure watch in the regular Fenix 8 and adds LTE for messaging, calls and LiveTrack – plus satellite messaging, check-in and emergency SOS for when you’re out of signal.The result is an even more impressive adventure tool for those that want to be phone-free.If you want to have someone keep an eye on you remotely while running out at night or in the middle of nowhere, the Garmin does so without needing anything else.It is quite freeing to be outside without a phone, but that capability comes at quite a cost, both in terms of the colossal price of the watch and the monthly subscription of the inReach plan to provide the service.At least it isn’t dependent on your phone provider so works with any brand of smartphone and network.

The Fenix 8 Pro is a killer device for someone who hates being weighed down by their phone when running, cycling or hiking, but still wants to be trackable and contactable.For everyone else, it is a lot of money when the excellent Fenix 8 already exists.Pros: LTE and satellite messaging, super-bright OLED screen, tracks everything with best-in-class GPS, built-in torch, phone and offline voice control, 8+ day battery life, Garmin Pay, full offline mapping and routes, offline Spotify, 100-metre water resistance and 40-metre diving, buttons and touch.Cons: extremely expensive, LTE and satellite features need monthly subscription, limited Garmin Pay bank support, voice features are slow, limited smartwatch features compared with Apple/Google/Samsung watches.