Diesel On Full Guard 2.5 review

A bold style choice, but a solid watch

Image Credit: TechRadar

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Specs and performance

  • Features the older Qualcomm Snapdragon Wear 2100 chipset
  • We found it to be tired in some respects, but overall good enough

The Diesel On Full Guard 2.5 works well, but it’s not the fastest watch we’ve ever used.

The Qualcomm Snapdragon Wear 2100 chipset used inside has been around for a couple of years now, and it's starting to feel a little tired in terms of day to day performance.

We wish the company had used the updated Snapdragon Wear 3100 chipset that is inside the Montblanc Summit 2 and Fossil Sport, but that doesn't mean this watch is unusable.

The Full Guard 2.5 can handle everyday tasks with ease, and while it won't blow you away with its speed it's unlikely you'll find this constantly frustrating to navigate around.

Other features on the watch include NFC, which allows you to make contactless payments using the Google Pay app. We found this to work quickly and efficiently - it’s a big benefit if you ever find yourself without your cards on a jog or a trip to the shop.

The watch also connected to the Wi-Fi easily, so you don’t always have to have your phone nearby to use it. It's worth noting that there isn't an LTE variant of this watch though, so you wont be able to get notifications and the like without your phone.


  • The latest Wear OS software is here ready and waiting
  • Works with latest iPhone and Android handsets
  • There's a specific Diesel app for exclusive watch faces

The Diesel On Full Guard 2.5 comes running Wear OS software, which means it’s compatible with both your iPhone and Android device.

It may take you some time to get used to, but Wear OS software works smoothly and allows you to download any app you find on the wearables section of the Google Play Store.

The Full Guard 2.5 gives you a plethora of watch faces to choose from as well as all those apps, and we like the way you can duck and dive around the software with ease.

If you’ve used an Apple Watch in the past you may find it a bit difficult to get used to Wear OS, but it shouldn't take you much effort as it's a similar sort of interface.

Swiping up from the bottom of the display will show all of your notifications, while down from the top will give you shortcuts to a lot of the key features of the watch. There’s then Google Fit when you swipe to the right and Google Assistant to the left.

If you press down on the crown, you'll be in the menu showing all the apps on the watch, which you can scroll through using your finger on the screen or by rotating the crown itself.

The core difference here to other smartwatches is the fact you can display Diesel watch faces. There’s an app to find these on the watch called Diesel T-On-I, and these change the main screen of the device to give it a unique and clear look.

This is a simple way to see all of your core stats such as your step count, your agenda for the day and what weather to expect. It’s not a core selling point of the watch, but you may find it an aesthetically pleasing choice if you’re a big fan of the Diesel brand.

Google Assistant worked speedily on the watch – or as quick as it does on other Wear OS devices – and we liked how you can quickly ask questions and get an answer over Bluetooth immediately.

Then there's the smartphone app that connects your watch to your phone. Compatibility wise, you'll be able to use the Diesel On Full Guard 2.5 in partnership with your Android device as long as it runs Android 4.4 or higher software.

It also works with a variety of iPhones, but if you've got an older device you may want to check the compatibility on the official Diesel website.

The app is easy to use, displays all of your fitness stats and allows you to add new features or change the settings of your watch with ease. You'll find this useful in setting up your watch and breaking down your fitness data, but apart from that we often found ourselves changing settings on the watch directly.


  • Includes a GPS tracker and heart rate monitor
  • We're unsure how comfortable you'll find this for exercise

It’s unlikely you’ll be buying the Diesel On Full Guard 2.5 as a full-blown fitness watch. There are lots of health features here, but the large design isn’t exactly ideal for a running watch.

Instead these are nice little additions that you may find useful to track your daily fitness or the odd run. However it does have GPS built in, so you won’t have to take your phone with you to track your location when out exercising with this strapped around your wrist.

Plus, there’s a heart rate monitor on the rear of the watch, which we found to be accurate and to work quickly.

The Diesel On Full Guard 2.5 is also waterproof, so you’ll be able to take this into the pool and track your workouts there. We haven’t yet tested the swim features of the watch, but these have worked well on previous Fossil smartwatches we’ve used.

Overall, don't buy the Diesel On Full Guard 2.5 for its fitness prowess, but instead think of this as a nice touch that gives you the added benefit of being able to check your heart rate or your step count.

Battery life

  • Lasts a whole day from a single charge, but not much longer
  • You may be able to stretch it to two days use with more limited usage

Battery is an area where the Diesel On Full Guard 2.5 struggles, and it’s one of the reasons we wish we had seen the company embrace the newer Snapdragon Wear 3100 platform.

We rarely got beyond a full day without the Diesel watch needing to be recharged again. 

With minimal usage you may be able to get two short days of use out of the smartwatch before needing to charge it, but every time we tried to go a night without placing it on the charging pad it wouldn't reach the end of the second day.

With more intensive usage – that's using GPS, notifications and other features – you’ll find the watch will last almost exactly a day.

This watch technically charges wirelessly, but you won't be able to use any Qi charger. Instead it uses a proprietary charger, so you’re going to have to remember to take that with you when you go away. 

Charging it up doesn’t take long though and we found it could charge from empty to full in around 90 minutes.

 Image Credit: TechRadar 

James Peckham

James is Managing Editor for Android Police. Previously, he was Senior Phones Editor for TechRadar, and he has covered smartphones and the mobile space for the best part of a decade bringing you news on all the big announcements from top manufacturers making mobile phones and other portable gadgets. James is often testing out and reviewing the latest and greatest mobile phones, smartwatches, tablets, virtual reality headsets, fitness trackers and more. He once fell over.