rexso explorer k full review

I still remember the time the cheapest 4k action camera was the Thieye T5e which costs over $100, which I wrote a review on.

Since then, many companies have broken this barrier and produced many action cams that are capable of taking real 4K videos, a few examples being the Yi lite and Mijia 4k.

Today, we’re going to be taking a look at one of the cheapest real 4k action camera, Rexso Explorer K, which also happens to be Elephone first real 4K action camera, and at the end, determining whether it’s worth the money or better off purchasing another camera.

Content of Review (Click to Skip To Section):


Specs Explorer K
elephone brand logo explorer k specs
Chipset HiSilicon HI3559
Image Sensor 16MP Panasonic MN34120
Video Resolution 4K 30fps
2K 30fps
1080p 30/60fps
720p 120fps
Photo Resolution 16MP - 4608 x 3456 (4:3)
Video Format H265 & H264
Stabilization 6 Axis Image Stabilization (Incl. 4K)
Battery 1200mAh
Accessories 1 x Waterproof case
1 x Bicycle Bracket
1 x Back clip
1 x fixed base
1 x clip
1 X Switch Support 1
1 X Switch Support 2
1 X Switch Support 3
1 x J-shaped Mount
1 X commutator
2 X Helmet pedestal
2 x bandage
4 x ribbon 2 x 3M Adhesive Tape
1 x wire cable
1 x USB Cable
1 x Cleaning Cloth
1 x User manual
Screen 2" LCD Screen
Storage Up to 128GB
Connectivity Wi-Fi, Micro-USB & Micro-HDMI
Best Buy: 89 USD On Gearbest (Flash Sale)

What It Comes With

explorer k accessories

It comes with all the basic accessories plus a storage bag.

The quality of the accessories is really good as they fit together snugly and securely.

Everything can be interchanged with GoPro, SJCAM accessories other than waterproof case as the button locations on the explorer K are slightly different.

Everything except micro-sd card is there already. My recommendation is to get a card at that’s at least a UHS U3 64GB micro-sd card. (Check my top recommendations here).


rexso explorer k body

The Explorer K has a rubbery side to it and a nice matte finish on the front.

It definitely feels more expensive and well-built than cheaper action cams (around $50) but when comparing to cameras like the Mijia 4K, its build quality still stands a little short.

Although the body resembles one of a normal action camera (matchbox style), it has one less button than traditional action cams, so if you’ve used other ‘normal’ action cams before, it’s going to feel a little odd. But otherwise, everything is pretty much the same.

Buttons, Ports & Indicators


rexso explorer k button

Power/mode button: Press to change modes; Press & hold to switch on/off.

Wi-Fi/back button: Press to change mode settings or for navigating; Press & hold to turn on/off Wi-Fi.

Shutter/select button: Press to confirm settings or start record/take picture. (depends on mode)


rexso explorer k ports

Micro-SD: On the bottom. Supports Micro-SD card up to 128GB.

Micro-USB: for charging and data transfer to PC.

Micro-HDMI: for displaying on the TV/monitor


rexso explorer k indicators

Led indicators is super bright so really easy to see: 2 on the front, 1 beside the shutter button

Status LED (Blue): Light On – power on; Light Off – power off;

Charging LED (Red): Light on – charging; Light off – fully charged

Top (Orange): Blinking: wifi switched on; Light Off – Wifi disconnected


rexso explorer k 2 inch lcd screen
Screen: 2 inch 320 x 240

I found it to be quite sharp & bright and it’s even pretty easy to see even in bright situations. That’s why it is in my opinion, one of the best screens I have seen of all the action cams I have reviewed.

Interface & Settings

Like I mentioned earlier, the navigation feels a little awkward initially because there’s only 1 button to navigate. (other action cams usually have 2 separate up & down buttons)

Nonetheless, after playing around, I got used to it and it still felt pretty natural and easy to navigate around.

rexso explorer k modes

There are 6 modes, record, photo, multi, settings, wi-fi & files.

Note: There is a typo error below which I have addressed to the support team.


Normal Video (4K 30fps, 2K 60fps, 1080p 30/60fps ), Slow-motion (720p – 120fps), Video time-lapse (0.5/1/2/5/10/30/60s), Video + Snap (3/5/10/30/60/300s), Loop (5/10/25 mins)


Normal Photo (16/12/8/5 MP), RAW (16/8 MP), Lapse – this is an error (it should be timer)(1/3/5/10/30s)


Timer – this is an error (it should be lapse) (0.5/1/2/3/5/10/30/60/300s), Burst (Up to 15p/s)


The settings isn’t that user-friendly because quite a few of the selections are in short-form and if you’re new to action cameras, it’d be a little hard to understand at first.

explorer k settings panel

Anyhow, there are 5 areas in the settings, media, photo, sd, system and info.

Note: There are some additional settings that came with recent update.


rexso explorer k media settings

Mic: On/Off sound recording

Flip: On/off Rotate the screen 180˚ for dash cam or other mounting use

OSD: On/off On-screen display

Encode: H.264/H.265

TV Mode: PAL/NTSC (No point because I’ve tried and it doesn’t change video frame rate)

Frequency: 50Hz/60Hz (No point because I’ve tried and it doesn’t change video frame rate)

LDC (Lens distortion correction): Digitally corrects fisheye effect

DIS (Digital Image Stabilization): 6 Axis Image Stabilization -Incl. 4K (Comparison Below)


explorer k photo setting rexso

Scene: Auto/Normal/HDR (I recommend using HDR here because auto doesn’t do a very good job)

EV COMP (Exposure Composition)±2 (Auto does a decent job)

WB (White Balance): Auto/Fluorescent/Sunny/Incandescent/Cloudy

Meter (Colour Meter): Center/Average

Shutter (Shutter Speed): Auto/2/5/10/15/20/30s (Very impressive, able to take long exposure shots)

ISO: Auto/100/200/400/800/1600


format sd card explorer kFormat: Completely erases and formats micro-SD card to be compatible with the camera


rexso explorer k system settings

Start-up mode: Off / Normal Record / Car Record (Loop Mode)/ Timelapse / Video + Snap / Lapse – Adjusts what mode it is in when it switches on

Auto Shutoff: Off / 1 min / 3 min / 5 min – auto power off duration

Auto Dormant: Off / 1 min / 3 min / 5 min – auto screen off duration

Language: English, France, Espanol, Deutsch, Portugues, Italiano, Chinese, Traditional Chinese, Japan, Russian, Korea, Polski, Vietnam

Time set: set the date and time manually (not required as it’s automatically synced with the app)

LED: switches the LED indicators on/off


explorer k info
Info from latest update

Shows the firmware version, model and manufacturer.


rexso explorer k wifi setting

Allows you to switch on/off Wi-Fi.


All your media and shots are stored here.

Unique Features

H.265 Encoding

explorer k h265 video decoding

This is quite unique because it has the ability to encode videos in h265 instead of the traditional h264 video encoding used by most action cams.

This is for the more technical people out there but in layman terms, it basically films at the same quality h264 but takes up smaller space (because of its more efficient compression algorithm) Therefore, you’ll be able to film way more at a go, without compromising any quality.

The only thing I can think that’s ‘bad’ about H265 video encoding is that it has a lower compatibility with technology as it’s still a relatively new technology. I had to update my Mac to the latest software update (Sierra V10.12.6) which was only released on Dec 2017 in order to be able to view and process H265 videos.

This is an example of a comparison I made to show the difference. I tried to make the clip as identical as possible to make a fair comparison.

h265 vs h264 video encoding

So as you can see, the difference is noticeable and for the same quality, you are able to save about 20% of memory space although this varies from one place to another.

All in all, a good addition to the camera as over the long run, it’ll save you a lot of storage and is definitely one of explorer K’s strong selling points.

6 Axis Image Stabilization in 4K

rexso explorer k 6 axis image stabilisation test

Stabilization performance to me is pretty good and especially excels when dealing with small tremors.

By default, it’ll be switched on. The only time when you want to turn it off is either when you want to save battery power or a larger field of view.

I was also genuinely surprised when it could stabilise 4K at 30fps as it is not possible with any camera at this price range (under $100).

So far, the cheapest action camera that can stabilise true 4K is Eken H6s, which costs 120 USD, followed by Yi 4K+ and GoPro Hero 6 Black.

Smartphone app – Explorer K (IOS/Android)

rexso explorer k app

The app is generally reliable and simple to use.

The interface is pretty standard, you can do all the normal stuff here, such as changing the settings, viewing live footage & remotely control the camera.

rexso explorer k app
Formatting & spelling error in the app

However, similar to the camera, there’re a few spelling and formatting errors in the app.

Overall, for the app, I felt it’s quite reliable, transferring speed is pretty fast and it’s simple to use as well. The only issue I had was the spelling errors and the general interface isn’t really visually appealing either.

Image & Video Samples

The Explorer K can take up to 16MP (4608 x 3456) 4:3 crisp shots but that’s just one of the thing we should consider in determining photo quality. Colour, low-light performance, raw image all play a part in deciding whether the quality is so-so or amazing.

Image Samples

explorer k image road with sunset
View original photo here.

As you can see from the shots I have taken, the 16MP definitely produces quite a sharp image and colours are pretty vivid and accurate too.  I felt it’s really good for a camera of this price range.

Raw Image – Weird Issue… (Fixed: Read below)

raw image fail rexso explorer k
Snapshot of RAW Image

The Explorer K is capable of taking RAW images but there is something strange going on here because despite having an option for RAW in the settings, when I try opening up with multiple software, it either comes up with an error or shows up a black image.
I’m not sure if there’s something wrong with it or could be memory card issue but I’m currently clarifying with the Rexso support team.

Video Samples

Stabilization (DIS) & Timelapse + Comparison With Mijia 4K


Explorer K & MiJia 4K –  Image Comparison

explorer k and mijia 4k image comparison
All images were set to auto and downscaled by the same ratio. Click here to download the original samples.

The obvious difference between the 2 is the field of view. Explorer K has a wider field of view (170˚), whereas Mijia 4K has a 130˚.

Also, if you were to look closer Explorer K definitely had an edge as it has more detail. Colours for both cameras had it’s strength and weakness so as far as colours go, they were pretty much on par.

However, overall, I would still go with the Explorer K’s for photo taking between the 2 as it takes a larger picture without compromising any quality.

Explorer K Vs Mijia 4Kmijia 4k and explorer k comparison

I feel the explorer K and the Mijia 4K is very similar because they fall in about the same price point of about 80 USD and are both capable of taking true 4K videos.

Overall, I felt that the quality of Mijia 4K is generally better than the Rexso Explorer K. Mijia 4K firmware is more stable, has a touchscreen interface, longer battery life and feels more well-built overall.

On the other hand, the Explorer K has a better screen (brighter and clearer), it also has way more accessories (Mijia 4k has none), takes at a higher resolution (16MP) and is able to stabilize at 4K.

Specs Explorer K Mijia 4K
explorer k vs mijia 4k mijia 4k vs explorer k
Max Image Resolution 16MP - 4608 x 3456 (4:3) 8MP - 3840 x 2160 (16:9)
Sensor: 16MP Panasonic MN34120 Sony IMX117
Video Encoding H265 & H264 H264
Chipset: HiSilicon HI3559 Ambarella A12
Raw image
Accessories Full Set
Screen 2" LCD Screen 2.44" Touchscreen
Field of view: 170˚ 130˚
Price: 89 USD On Gearbest 89 USD On Gearbest With Code: GXBX01

Firmware Bugged Out! – Fixed By Hard Reset

After testing for a few days, everything went pretty much perfect but suddenly, for some apparent reason, it became irresponsive as you can see from the above video.

I suspected this was due to using an ‘inappropriate memory card’.

Awesome Customer Service Team!

I immediately contacted the technical team and within a day, they replied and went through the steps to hard reset with me.

It worked and that’s why I’d like to commend them for their responsiveness as many Chinese companies honestly wouldn’t even have cared about you after sales, but Rexso proved that they were not ‘one of them’!

Anyways, this shouldn’t happen to you as I was experimenting what would happen if I were to use a memory card not on the recommended list and turned out it bricked the camera. lol

Performing Hard Reset

The steps are pretty standard to other action cams.

  1. Unzip this file (download here) and copy the contents to an empty memory card.
  2. Insert the memory card into the camera.
  3. Press and hold the power button and shutter button together until the blue light flashes. (about few seconds)
  4. The camera should startup automatically within a few minutes.

Download the latest firmware update and receive the latest updates from the Explorer K Facebook community!

Feel free to post your thoughts or problems (if you have any) in the community. Join here!

Where To Buy

Best Buy Price
110 USD


The Rexso Explorer K is definitely a unique action camera because no other action cam that costs under $100 has native 4K recording capability, H265 encoding, full accessories kit and stabilization at 4K.

The build quality is also pretty good, buttons are responsive, the screen is one of the best I’ve seen.

There aren’t any major issues except that it overheats relatively easily and the part where there are glitches regarding H265 video and raw image. Also, other than the minor spelling errors which can be all fixed through a firmware update, I think it is one of the best 4k action cameras for your money.

Should You Buy It?

If you’re finding a decent 4K action cam that comes in a complete set, I’d definitely recommend getting this. It’s really everything you’ll need! (except for the memory card which you can get here)

Although there are some issues faced by the camera, it’s really only temporary as the support team are really responsive and quick at solving these issues.

Having said all of that, for me, I’d still go with the Mijia 4K because of the touchscreen capability and ‘cleaner’ camera interface despite the lack of accessories, stabilization in 4K and the higher quality of images which the Explorer K can offer.

Meanwhile, there’s another action camera that is very similar to the Mijia 4K and Explorer K, the Explorer 3 by MGCOOL. I’ll be doing a review on it once I get my hands on that! Stay tuned!

This concludes my review for the Explorer K. What are your thoughts on this? Do you have any questions regarding it or action cameras in general? Any Feel free to leave a comment down below!

That’s all for now. Until next time, thanks for reading and have a great day! 🙂

Rexso Explorer K

89 USD

Video/Image Quality


Build Quality


User Experience


Bang For Your Money


Audio Quality


Smartphone App



  • H.265 Decoding Capability
  • Amazing True 4K Image Stabilisation
  • Comes with tons of accessories
  • Clear 16MP Photos
  • Responsive Customer Support Team


  • High Operating Temperature
  • Spelling Errors in App & Settings Page
  • Can't shoot in PAL (50Hz) Power Frequency
  • May Bug Out If Use Non-Recommended Memory Cards
  • Raw Image & H265 Bug

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