Sigma Rox 12.0 Sport review

In the pre-GPS age, Sigma was the undisputed king of bike computers, making smart simple units that were fully featured and easy to use. The Sigma Rox 12.0 Sport takes a lot of that original common sense and applies it to the design too.

The Rox 12.0 Sport’s excellent package includes a quality out-front mount, a standard bar mount, an HRM strap, and a speed/cadence sensor along with a good length cable. It might seem like simple stuff, but when you’re paying these sorts of prices you want everything thrown in.

The mounts are like a stiffer quarter-turn Garmin mount and are actually cross-compatible. I tried the Garmin Edge 830 and 1030 on them, as well as the Sigma on the Garmins’ mounts along with some aftermarket quarter-turn mounts too.

Sigma Rox 12.0 Sport in use

When you switch on the Sigma it looks every inch the quality item with a high-res, bright and clear touchscreen. It runs on an Android-based operating system, but you can’t add apps to the unit, though it’d be interesting to see that available – having Strava native on the device for instance could be a gamechanger.

However you look at it though it means – unlike plenty of its rivals – the Rox works completely independently of your smartphone (iOS or Android) with the only connection made through the Sigma Link app. Rides can be uploaded automatically to Strava too.

The Sigma Link app is as basic as it comes, it’s really just a database of activities and routes from either the device or your connected apps (Komoot, GPSies, MyTracks). Sigma also has a Data Center web-based program, which offers a much more comprehensive suite of analysis tools.

The Rox 12.0 has no Bluetooth connectivity and is completely reliant on WiFi. You can download some very detailed mapping courtesy of OpenStreetMap, which can come as some seriously large tiles – one area stretched from the outskirts of Cornwall to the west, another to mid-Wales, and the Midlands to the north, while there was also outer London to the east, and to the south coast.

The device is fully compatible with TrainingPeaks, Strava, Komoot and GPSies and has touchscreen tabs on the menu screens to take you to the routes. You can also log into your TrainingPeaks plan and even compete in Strava Live segments too.

Connecting with sensors is a breeze – it communicated quickly and easily with my Di2 test bike, plus Shimano power meter, SRAM eTap and eTap AXS, Quarq power meter (Red eTap and Force AXS models) and HRM strap, along with Wahoo’s Tickr and a Garmin Vivosmart (in HR transmit mode).

Sigma Rox 12.0 Sport routes and navigation

Navigation is excellent, with a good search that offers suggested routes, a shortest route and an easiest route.

You can create routes by address, point of interest, coordinates, or a point on the map. Only the points of interest showed any oddities when I asked it to take me to Wiltshire’s Longleat estate, with its route suggestion being a high street in a nearby town.

You can also route by adding points on the touchscreen scrolling map, or draw the route directly onto the screen with your finger, although I’d recommend some sort of stylus because thick fingers on the small screen can be frustrating.

The way it pings your rough route to roads and trails (if you’re in off-road mode) is pretty clever too. As with Garmin, you can set the bike type before a ride, with customisable settings. The screen clarity is great, and the gradient graphs and the map screen are high in detail and rotate quickly to your direction of travel.

If you deviate from your set route the Rox 12.0 quickly adjusts and won’t try to loop you back, instead it will find a route back to your track quickly and efficiently in the same manner as Garmin’s 1030 and 830.

Sigma Rox 12.0 Sport features

GPS pick-up is quick at between 20 to 22 seconds. The customisation of standard functions such as backlight timing, altimeter calibration, sleep timing (where the unit shuts down when not in use), and switching between imperial and metric is all easy to do.

The Rox is neatly communicative too, with full-screen prompts that come up when you're moving, when it’s paused and when your battery is low – you’ll never have the issue of not recording a ride by accident either.

Although the Rox relies on the touchscreen a lot, it does also come with secondary buttons – the On/Off button is high on the right flank and below the screen is the Garmin-esque Start/Lap button, and a Stop button too.

At the base of both flanks is a large button for scrolling between screens. This is a nice touch when you’re wearing thick winter gloves that aren’t quite as touchscreen-compatible as you’d like.

Sigma states an IP67 waterproof rating for the Rox 12.0, which means it can be submerged in water one-metre deep for half an hour – it’s a pretty bold claim especially when the base of the unit has (tight-fitting) rubber covers for both the micro-USB and SD card slot.

When brand-new I’m sure these are pretty watertight, but after a few months of pulling and pressing back in, I’d be concerned they’d be a bit loose.

Sigma claims up to 16 hours of run-time for the Rox 12.0, and if you were using the unit in a bare-bones way then that may be possible, but while running a full suite of sensors and navigating too, the Rox gave me a full-screen low-battery warning after just shy of seven hours.

Sigma Rox 12.0 Sport overall

The Rox 12.0 is a serious rival to some of the most high-end bike GPS devices, including the Garmin Edge 1030. The screen clarity is brilliant, the interface is easy to use, the navigation and the accuracy of tracking is superb too.

The downsides are few, but having no direct Bluetooth communication with a smartphone is an issue because you’ll need a WiFi hotspot to download routes or upload rides.

The Sigma Link app is a bit basic and if you’re already using Strava, it’s sort of superfluous too. However, the Rox is unique in the world of GPS and with a few improvements it could very well be one of the best.