A few weeks ago I wrote a preview article introducing the Yi 4K action camera. The upstart Chinese company has boldly promised that their top of the line $249 action cam can outperform the GoPro Hero4 Black (the Hero5 Black had yet to be announced when I began testing) which sells for $100-150 more.

That's a pretty bold statement considering that GoPro is a name synonymous with action cams, so much so that many people call any action camera a GoPro. I've spent the last few weeks testing that claim, and you know what, the Yi 4K is not as good as a GoPro Hero4 Black. It's better.

The Good

Touchscreen Facilitates easy setting adjustments and allows for preview and review of shots.
Video quality Quite good, on par with GoPro.
Battery life Excellent for an action camera.
Price Incredible value at this price point.
Android application It has a couple quirks, but it's fast and functional.

The Not So Good

No included accessories A charging cable and battery are all that come with the camera.
Dim status LEDs Like myself, they would be better if they were brighter.
Memory card slot The memory card slot is recessed alongside the battery and is difficult to access.
No water resistance Without a protective case (sold separately) the camera has no water or dust protection.
Poor image stabilization The electronic image stabilization of the Yi 4K doesn't do much of anything.


Processor Ambarella A9SE
Image Sensor SONY IMX377, 1/2.3", 12 megapixels
LCD Screen 2.19", 640x360 resolution touch screen, 330ppi, 16:9
Lens F2.8 aperture / 155°
Wi-Fi 5GHz /2.4GHz
Battery 1430mAH
Weight 3.4oz
Dimensions 65 x 42 x 30 mm
Features Loop recording, time-lapse video, electronic image stabilization, lens distortion correction
4K 30fps
2.5K 30fps
1440p 60, 30fps
1080p 120, 60, 30fps
960p 120, 60fps
720p 240fps

Design and build quality


To begin, let's address the elephants in the room. First, the Yi 4K looks quite a bit like a GoPro. The waterproof case is also nearly identical the GoPro's, the sounds it makes are the same, it uses the GoPro's mounting system, and both the camera's UI (compared to the Hero4 Silver) and mobile application also bear a striking resemblance to GoPro's offerings. If imitation is the sincerest form of flattery, then the folks at GoPro must have blushed like a teenage boy getting a hernia check when they saw the Yi 4K for the first time.

Yeah, there are some things that may have been, well, borrowed, from GoPro. Whatever – we'll let Yi and GoPro's lawyers figure that out. I just wanted to put that out there before we proceed.

Now for the second elephant. I tested the Yi 4K against the GoPro Hero4 Black, not the newer Hero5 Black. Why? Because the Hero5 Black didn't exist when I started working on this project and there was no way I was going to go back and start it all over again (it's already been the most time-consuming review I've ever done for AP). Sorry if that's disappointing. If it makes you feel any better, from what I have read, the video quality of the Hero5 is almost identical to Hero4, so the footage I've captured should still work just fine as a comparison.

Ok, now that we've addressed the pachyderms, let's shift our focus to the star of this review, the Yi 4K action cam. Shall we begin with a tour?



The most notable feature on the front of the Yi 4K is the lens which protrudes about a third of an inch on the far right of the device. On the far left sits an LED that changes color to indicate the camera's current status. The LED isn't terribly bright and is difficult to see in direct sunlight. It's even harder to see when the camera is closed within its reflective waterproof housing.


A 2.2 inch LCD touch screen protected by Gorilla Glass stretches across the entire back of the device. It sports a resolution of 640 x 360 pixels (330ppi), which is plenty sharp for a screen of this size. With its 16:9 aspect ratio there's no letter-boxing of footage captured on the camera – a smart design choice. The shape of the screen also affects the shape of the camera as a whole. While it is almost the same height and thickness as the Hero4 Black, the Yi 4K is approximately 25% wider.


The color accuracy of the screen isn't perfect, the white balance is a bit on the cool side to my eyes, and it could use a few more nits of brightness to help with visibility outdoors on a sunny day, but all told, it works pretty well.

Top and bottom

Across the top of the camera are holes for the dual microphones and speaker and the shutter button – which is the only physical button on the device. An LED light in the center of the shutter button turns red when the camera is recording, which like the screen and other LED, is frustratingly too dim.


On the bottom is a sliding door which, when open, exposes the battery compartment and MicroSD card slot. The SD card, once inserted, can be a pain to access and requires some long fingernails or something else pointy to eject the chip. A standard tripod mount is also located on the bottom right of the camera, a feature I always love to see.


The left side of the device is bare and a small flap covering the MicroUSB charging port is the only thing found on the right side of the camera. I appreciate that the flap is connected to the camera by a small piece of plastic, unlike the one covering the port on the Hero4 Black that can easily be lost. It's also nice to see a charging method as ubiquitous as MicroUSB employed.


Overall, the build quality of the Yi 4K is great. The parts all fit together well, the plastics are high-quality, the button has nice, clicky feedback, and it feels solid in-hand. That's good, because even though it's cheaper than a GoPro, $250 is still a pretty hefty chunk of change and I expect top notch build quality for that kind of money.


There is simply no comparison here, the Yi 4K is sooo much easier to operate with its touchscreen than the Hero4 Black's three button plus LCD setup. I hadn't used a Hero4 Black before this review, and man, I don't know how it could be the top dog in the action camera world with such terribly unintuitive controls.

Seriously, I loathed changing settings on that camera. I would inevitably hit one of the buttons incorrectly, switching modes instead of frames per second or something else similar almost every freakin' time. Granted, this was my first experience with a GoPro, and I'm sure if I had used it more I could have gotten used to it, but yuck, no thanks. I never did understand how the lower end Hero4 Silver model was graced with a touchscreen while the more expensive Black was spurned. The good news here for GoPro fans is that the Hero5 Black has a touchscreen, so this particular advantage of the Yi 4K is now moot.


Controls on the camera are intuitive and easy to use. The touchscreen is responsive and had no issues recognizing my commands. The only time it gave me any problems were occasions when I tried to use it with damp hands, which is a normal problem for any touch screen. The settings are laid out in an intuitive manner which makes changing settings on the fly super simple. There are six different shooting modes, three for photos, three for video, and a plethora of different settings for each.

There are a couple of shooting modes on the GoPro that are omitted from the Yi 4K, most notably the option to shoot at 24fps, which gives video a more cinematic look. The Yi also has a couple of shooting modes not present on the Hero4 Black, the first is the image stabilization mode (which the Hero5 Black now has) and the second mode corrects lens distortion (also known as the fish-eye effect). I'll show you how well those work in the video sample section.


Having a touchscreen to adjust settings is great. It's also wonderful that you can use the screen as a viewfinder for framing shots. Being able to do this without using a companion device is extremely convenient and saved me from having to repeat shots during testing due to an incorrect angle, lens flare, or other issues.

While I'm mostly content with the Yi's controls, not all is sunshine and daisies; there is one problem. Once you put the Yi 4K into its waterproof case you can no longer operate that wonderful touch screen. That means no changing settings when you are underwater, or in a place where you don't want to risk exposing your camera to muck or moisture. You can still change settings through the smartphone app, but that's hardly helpful when you're snorkeling. Big deal? Probably not for most people, but definitely worth mentioning.

Battery life

My word, I had read that the Hero4 Black had poor battery life, but I still wasn't prepared for how horrid it really is. I was lucky to get a little more than an hour and fifteen minutes of mixed recording from the GoPro during my testing. With a battery munching LCD screen spanning across its back, I expected the Yi to have about the same, or maybe even slightly worse, longevity as the GoPro.


I was pleasantly surprised to discover that the Yi 4K actually has substantially better battery life, even with the touch screen. How much better? About twice as good, averaging around two and a half hours of use per charge. Granted, the battery is slightly larger in the Yi, which makes the camera a little bulkier than the GoPro, but if a slight size increase lead to doubling the battery life of the Hero4 Black then the decision to make the camera a little larger was the right one.


The Yi 4K doesn't ship with anything other than a USB charging cord (you even have to supply your own power adapter). That's a letdown considering that the Hero4 Black includes a waterproof case and a few mounting clips. The official Yi waterproof case, which is compatible with GoPro's mount systems, will set you back $40.

If you consider a waterproof case a necessity, as I do, it raises the total cost of the camera to almost $300. That's just a hundred bucks less than the new Hero5 Black (which doesn't include an underwater case either, but is waterproof without a shell to depths of 10m) and makes the Yi seem like less of a bargain.

There are a limited number of official Yi accessories available for purchase, but I can't attest to the quality of any. The waterproof case and the mounting shell I used in my testing are both made by a third-party company, and were not built to the same standards of quality as the camera. In fact, the clasp on the waterproof case popped off several times during my testing and was a real pain to use.

Although they are more expensive, I'd recommend sticking to official Yi accessories, which can be found on Yi's storefront on Amazon. If you want to take a walk on the wild side and try some cheaper imitation accessories, or head over to GeekBuying, they have several to choose from.

Android application

I'm pretty impressed with the Yi Action Android app that serves as a companion to the Yi 4K. It took a couple of minutes to configure the WiFi settings the first time I connected the camera to my Nexus 6P, but since then it has paired within seconds every time I have used the application. That's impressive considering the GoPro had trouble connecting to my phone on a couple of occasions.

Once connected, the Yi app excelled at the three tasks that are most essential for an action cam app. First, it functions great as a second screen, with low latency (thanks to its fast 5GHz WiFi connection), great range, and quick response to input. Second, the app provides full control over the camera settings. Every setting that can be adjusted on the camera proper can also be changed through the application.

Third, the companion app facilitates easy wireless transfer of images and videos from the camera to a phone or tablet. You can even trim videos and apply filters and music in the application before downloading them. I wish the process were a little quicker, but 4K video files can be massive, so I can't complain too much.

screenshot_20161019-090218 ti-ap-1 yi-ap-2

There is also a social media component to the application which seems to facilitate the sharing of videos captured on Yi action cameras. To be honest, I didn't give that portion much more than a cursory glance as it is something that I doubted would interest most of you. The best thing I can say about that portion of the app is that you mercifully are not required to create an account in order to use the truly useful parts of the application.

Video quality

Ok, here's the part of the review of greatest importance. Battery life, form, and controls are all well and good, but what really matters in an action cam is how well it can capture video. A lot of inconveniences can be forgiven if a camera can flat-out outperform its rivals in image quality.

Before I jump into video comparisons, I wanted to quickly address my methodology. Based on your excellent feedback from my preview article I crafted my very own Action-Camera-Comparisonator!


I'll give you a moment to compose yourselves after beholding such a beautiful piece of craftsmanship. Alright, so it looks like something a ninth grader built during shop class, but hey, it got the job done. With my ACC (Action-Camera-Comparisonator) I was able to shoot video with both cameras at the same time from almost the same position. Every comparison shot that follows in this review was captured while the cameras were secured to the ACC.

In order to mount the GoPro Hero4 Black to the ACC, I had to put it in its protective housing, but I used the door with an open back to ensure the best audio capture possible.

I used the default color-balance mode on both cameras and didn't change any settings other than resolution. The videos have not been altered in any way during editing. With that established, let's take a look at some footage and I'll provide a bit of commentary. Mostly, I'll just let the videos do the talking. Keep in mind, I am not a professional videographer, so I may not notice things that a more trained eye would.


Wow, those videos looks pretty much identical. The way the cameras adjust to changing light, their color balance, sharpness, and contrast are all nearly indistinguishable. It was honestly challenging keeping track of which video came from which camera when I was editing, they are that similar.

Sound capture is tougher to compare between the two cameras. The Yi microphones pick up more subtle sounds, but are easily blown out by wind noise. That may just be a result of the different styles of housing that I used on the two cameras during testing.


More of the same here. Image quality is nearly indiscernible. Unfortunately, neither camera's video looks anywhere near as good on YouTube as it does when played on my home computer, but hopefully you can get the idea.

Slow motion 720p 240fps

Slow motion video capture is a clear win for the Yi 4K. Both cameras suffer from a decrease in sharpness and contrast when capturing video at such a rapid frame-rate. Where the Yi excels is with its field of view, which is still the full 155 degrees instead of being drastically cropped as the GoPro footage is.

This is particularly evident in the final shot of the stick breaking. While the stick is at the center of the shot in the footage captured by the Yi, the GoPro captures only a fraction of the shot. I would have been able to correct for this when capturing the video, but without a screen on the GoPro I didn't realize the shot was cropped so tightly until after I got home and started reviewing footage.

Time lapse

Once again, image quality is nearly identical.

Electronic stabilization and fish-eye reduction

This video isn't a comparison between the Yi and GoPro. Instead, I took a couple of shots to show how well a couple of shooting modes specific to the Yi 4K work. The first portion of the video shows the difference between shots taken with and without electronic stabilization and the second demonstrates how well the fish-eye reduction feature works.

Did you guys see any effect from the electronic image stabilization? To my eyes, it doesn't seem to do much of anything. That's a disappointment, especially since I've read that the EIS on the Hero5 Black is quite good. The fish-eye reduction on the other hand works well. It does crop the shot slightly, and causes a little warping at the edges of the frame, but I think it still looks better than the first video with bendy trees.

Demonstration of full capabilities

The little video clips I've shown you thus far are good for comparison's sake, but are not terribly exciting. To truly test this camera I wanted to film something more exciting to demonstrate how well this camera could perform in adverse conditions. Luckily, my cousin Joe invited me to go on a two-day tuna fishing trip with him last month, which was a perfect opportunity to put the Yi 4K through its paces. I shot over six hours of footage during the trip and spent several hours after I got home compiling the footage into a short video to share with you. Warning, the video is a bit on the graphic side – tuna bleed like crazy when they are caught. If you don't like fish violence, skip the part from 2:20 to 4:03.

That looks pretty dang good if I do say so myself. It's even better when you consider that was stitched together by a guy (me) who had never used Adobe Premier before last month. I'm sure someone with real video editing experience could have made the video look even better.

Still image quality

Action cameras are geared toward capturing video in extreme conditions. They are not designed to take great still images, and capturing and comparing images from the Yi 4K and GoPro confirmed that. With excellent lighting, the cameras are both able to capture a somewhat decent 12MP photo, but any modern smartphone (by that, I mean one built in the last three years) will easily outperform either camera.

For what's it's worth, I found the still image quality of both devices to be pretty similar. Similarly crappy that is. Both produce noisy, grainy, and fish-eyed, images. The GoPro's pictures are just a touch better looking to me, with more accurate color and less fog, but both devices are so underwhelming in this regard that that's hardly a compliment.

Bottom line, I wouldn't buy either one of these cameras for taking stills, they both are pretty lousy at it. I included a few comparison photos so you can see for yourself. The first image in each set was captured by the Hero4 Black, the second, by the Yi 4K.


When I accepted the invitation to compare the Yi 4K to the GoPro Hero4 Black I was very skeptical. There are a lot of cheap GoPro imitators out there, and most of them are garbage. I honestly thought that the Yi was going to be trounced by the more expensive, and far better known, GoPro. Those preconceived prejudices began to crumble within just a few hours of using both cameras. This little camera is excellent. It doesn't perform as well as its pricier competitor, it performs better.

Image quality and the mobile applications usefulness are about equal between the two cameras. Battery life and controls are both major wins for the Yi 4K, as is the overall value. The GoPro may have some advantages to professionals that I'm not knowledgeable enough to recognize, but for the average guy who just wants an action cam to record his adventures, the Yi will do just as good a job for less money. Now, having not spent any time with the Hero5 Black, I can't definitively say that the Yi 4K is better, but I can tell you it's cheaper. I can say that I'd take the Yi 4K over the Hero4 Black, even if they both cost the same.

I'd like to thank GeekBuying.com for supplying the demo unit that I used for this review. If you would like to purchase a Yi 4K action camera you can purchase one tax free at GeekBuying.com or through the Yi store on Amazon. It sells for $249 and is available in black, white, and light pink.