Viofo A139 Pro Dashcam Review

Viofo A139 Pro Featured


  • Wonderful video quality
  • Great lenses
  • Nice wide angle of view
  • Amazing image quality


  • App a little bit finicky on Android

Our Rating

8 / 10

Dashcams are not something I initially wanted, but oddly enough, I recently shopped around for one, as I had heard a rumor that having one in your car can have a positive effect on your insurance premiums. My curiosity turned into interest when I was sent the Viofo A139 Pro Dashcam for review. I have to admit that when I was watching back its footage, it was the first time I've ever said "Wow" out loud when describing image quality on a dashcam or action cam.

This is a sponsored article and was made possible by Viofo. The actual contents and opinions are the sole views of the author who maintains editorial independence even when a post is sponsored.

Moving Movies

The Viofo A139 Pro Dashcam is a true 4K dashcam with the ability to record the world outside your car in case of accidents – like a security camera system on the move. The unit boasts Full UHD 4K with a new Sony sensor that offers a wider dynamic range and much less noise and motion blur during day and night recording than other competing dashcams.

It offers better night vision, too, due in part to the extended dynamic range, I suspect. The unit I received was the three-channel version with the optional interior camera.

Viofo A139 Pro Packshot

Inside the box, you'll find:

  • A139 base unit with fancy Sony camera attached
  • Rear camera
  • Interior camera
  • Adhesive stickers for placement on expensive glass car windshields
  • Several kilometers of cabling to attach the smaller cams
  • Nice quality metal USB plug
  • Pry bar for removing the mounting adhesive pads
  • Polarizing filter for the front lens
  • HK3-C Hardwire Kit for wiring into the fusebox
  • Wireless Bluetooth remote control button

Lights, Camera . . .

Dashcams are always sold by their resolution, but in truth, what really makes the difference is clarity. The first thing I noticed when poring through the documentation is that the main forward-facing camera is driven by the Starvis 2 Sensor, an 8MP 1/1.8 IMX678, but the rear and interior cameras are based on the older Starvis sensor, the original 2MP IMX291. To be clear, you only get the strongest image clarity on the front camera. This is, however, the first dashcam based on the Sony Starvis 2 IMX678 image sensor.

Viofo A139 Pro Rear And Interior Cam

That's not to say that the rear and interior cameras are bad, as they are not, they are really good. They just don't match the low-light, dynamic range and ultra-clear performance of the better sensor up front. In general, the image quality from the front camera is superb 4K UHD, while the rear and interior are merely very good HD.

In case I haven't made it clear, the image quality of the videos is superb, even from the lower-resolution cameras. It's some of the finest quality I've seen from small cameras. There must be some stabilization tech in the cameras, too, as the output is really steady and smooth, no matter how many potholes you drive over.

Viofo A139 Pro Footage Front

There are also options you can set up for parking. When you leave your car parked in the city, for example, you can check to see if anyone bumped into your car while they were parking beside you. There is also a time-lapse option to avoid taking up too much card space.

Viofo A139 Pro Footage Rear

The Viofo lenses are quite impressively good for the price, so they make the Starvis 2 chip shine. The overall image quality is really decent. There is a tiny bit of chromatic aberration (the tiny red and blue lines on the left and right sides of objects with contrast) but nothing too horrible and only visible to nerds like me who zoom in. In normal use, you'd never see it. The lenses are, for the purposes of the job they have to do, sharp and clear. The best bit about clear pictures is capturing all of those lovely registration numbers and faces of people that run into you.

Obviously, the interior cam will be popular with YouTubers and TikTokers who like to do car karaoke, so that's another use for the system that I wasn't previously aware of.

Viofo A139 Pro Phone App

For live viewing, the device has a custom phone app that gives you live streaming via Wi-Fi and the ability to view the streams as picture-in-picture. I found the app to be useful but too distracting to have running on the dash. I also found it dropped the connection to the camera a few times, but that could be my phone. The app doesn't record the videos but can be used to download and share videos from the dashcam base. The recordings are stored on the camera itself, as separate videos on the internal TF card for viewing or copying to your PC via a TF card reader.

. . . and Action!

Using the system is really easy: the device powers on and starts recording as soon as you turn the car on and stops gracefully when you turn it off. It chimes and verbally states it's recording and mentions the quality. The videos are recorded in one-minute chunks to ensure that they are not corrupted during the booting up and down process. This makes reviewing them a little difficult, as it records MANY clips, but if you use the Movies and TV viewer on Windows, you can forward to the next video easily.

Viofo A139 Pro Installation Front

Installation is not a trivial exercise, if I'm to be honest. Sticking the cameras on the windows of the car is relatively straightforward. As the permanent 3M adhesive pads on the devices are so strong and permanent, Viofo cleverly supplied transparent stickers to help reposition the cameras if you get the placement slightly wrong. Apply the stickers to the window, then apply the heavy-duty 3M sticky pad to the sticker. If you get the placement slightly wrong (which you almost certainly will, as it's awkward) you can peel back the sticker and replace it without problem.

Viofo A139 Pro Cables

As with most dashcams, you have to power the unit from the cigarette lighter/accessory power socket, and the wiring has to trail from that under your dash, up one of the window posts and across the top of the windshield. Running a cable from the front of the car to the rear camera is even more of a challenge. Getting the cable tucked away so that it doesn't interfere with entry and exit and any of the car's systems is a bit of a pickle but not impossible.

Final Thoughts

In summary, despite the general concentration on specs, etc., where dashcams and action cams are concerned, I think the thing that really makes the difference is, as it always is with any camera, the optics. You can have the most impressive specification sensor in the world, but put a crappy lens on it, and you get rubbish pictures. Clearly, the output here is anything but rubbish and is quite stunning.

Viofo A139 Pro Main Unit

The Viofo A139 Pro Dashcam is an excellent premium dashcam, solidly built and with great quality captures. I think the front lens is a bit too wide if anything, as there's a small amount of vignetting, but it's a security device, so coverage is everything. It grabs in everything in what looks to be about 45 degrees.

Overall, I really enjoyed using it, and it did the job beautifully and without any assistance from me. If you'd like to purchase your own, the retail price is $399.99. It's also available in a two-channel pack with either the rear or the interior camera and a standalone version at $329.99 and $259.99, respectively.

Phil South
Phil South

Phil South has been writing about tech subjects for over 30 years. Starting out with Your Sinclair magazine in the 80s, and then MacUser and Computer Shopper. He's designed user interfaces for groundbreaking music software, been the technical editor on film making and visual effects books for Elsevier, and helped create the MTE YouTube Channel. He lives and works in South Wales, UK.

Subscribe to our newsletter!

Our latest tutorials delivered straight to your inbox