Review LG K51S: interesting, but without differentials [análise/vídeo]

LG wants to grow in the mobile segment and, for this, is betting heavily on the K line: K41S, K51S and K61. THE LG K51S is the family intermediary with a suggested price of R $ 1,500. We can say that it is a better version of the K12 Max and successor to the K50S.

In comparison with the brothers K41S and K61, the K51S does not have so many differentials. It delivers a quad camera, a 6.5-inch HD + large screen, long battery life (4,000 mAh) and the processor is the same as the K61, a MediaTek Helio P35.

More camera, more battery, more screen. These are the pillars that LG seeks to win over young audiences with the new smartphone and, thus, hopes to stand out in the segment. Remembering that brands like Samsung and Motorola are already betting on the “three more” – and it is not today. I spent a few days with the new LG K51S and tell you everything I thought of it below.

Review of the LG K51S on video


The LG K51S has a premium look that even refers to other company devices and even other brands, such as the Samsung Galaxy S10. Here, the LG smartphone is for sale in two colors: red and titanium, which I received for this review. It is a color that resembles graphite and, at the same time, has a mirrored effect. However, the fingerprints can be a pain in the butt.

Although it looks like glass, the cell phone body is all plastic and LG can “cheat” well, because, during the first impressions, I thought it was glass.

It is worth remembering that we have a Military Resistance certificate here, that is, it is resistant to impacts, humidity, thermal shock, among others.

Behind, the device has four lenses. From left to right, they are: a 2 megapixel macro, a 5 megapixel Super Wide Angle, a 2 megapixel depth sensor and a 32 megapixel smart camera. In the fifth hole, there is the LED flash.

LG K51S fingerprint reader

LG placed the fingerprint reader on the back of the device and the company logo was positioned at the bottom. On the right side, you will find the power button and the tray to insert the chip and the memory card (nano-SIM + nano-SIM + MicroSD). On the left side, there are the volume buttons and a dedicated one for Google Assistant – also present in previous devices, like K40S and K50S.

I said that LG wants to win over young audiences, right? Well, the button for Google’s virtual assistant was not added for nothing. The company wants to make life even easier for the user, who is always connected and increasingly using resources like this.

LG K51S with Google Assistant

At the bottom, LG introduced the headphone jack and USB-C. In the same area is the speaker.

Screen and sound

The LG K51S has a 6.5-inch IPS LCD screen with HD + resolution (720 x 1600 pixels), with a 20: 9 aspect ratio. Considering that the K51S is the successor to the K12 Max, we can say that there has been a considerable improvement in screen size here.

LG K51S screen

However, they are the same settings as the entry version, K41S. The exception is in the selfie camera, located in the upper left corner in a hole in the display, which I like a lot. On the K41S, LG opted for the drop-shaped notch to house the lens.

The screen is not as bright, even at maximum brightness. I even used the cell phone all the time with 100% brightness during the day.

Unfortunately, the immersion may not be as complete in some applications, such as Netflix, which does not occupy the entire screen of the device, unlike YouTube videos and some games.

LG K51S screen

LG had almost everything to win me over with this display, but an inaccuracy in the LCD, where the selfie camera is located, intrigued me. Around the lens, there is a black “stain”, noticeable on pages and white background applications. Initially, I thought it was just a problem with the device that was with me, but I realized that this gradient is present in the K61.

LG K51S speaker and USB-C port

As for the speaker, the sound is clear and balanced, except at high levels, since some distortions and treble arise. For those who consume a lot of audiovisual content on their cell phones, the LG K51S comes standard with DTS: X 3D Surround, which provides an immersive audio experience.

It is a technology already present in the LG G7 ThinQ and that worked very well here in the K51S. I even used a headset with DTS: X 3D Surround enabled all the time – it basically looks like you’re in a movie theater (when watching movies / series) or in a music studio (when listening to music on Spotify).


The LG K51S arrived for us running Android 9 Pie. For now, the company does not share a date to make Android 10 available – and the same goes for old brand phones. But speaking specifically of K51S, the software here is simple and there are no complex features. I liked that the setup is lean, which means you’ll find what you need quickly.

Android 9 Pie

The interface is the same as the LG G8X and, unlike other Androids, the K51S does not have a drawer with all applications. And by the way, it comes with few apps installed: Google apps, Facebook, Instagram and some games (DragonMania, Empires, Asphalt Nitro, Little Big City 2 and Pastry).

In short, I really liked the interface of LG’s intermediary: there is night mode, the notification bar is organized and it is also feasible to use two applications at the same time thanks to the multitasking window function. It is also worth mentioning the camera application, which is very complete. Which brings us to the next item:


The camera set is the highlight of the K51S. LG likes to point out that it is giving the user the complete kit of a photographer. Well, let’s see next:

The four lenses of the LG K51S

The main difference of the K51S compared to the K41S is to bring a 32 megapixel smart camera – the same lens on the K41S has 13 megapixels. It has an Artificial Intelligence (AI) feature similar to the Huawei Nova 5T, which can detect the object to be registered and apply adjustments before you take the photo.

With this technology, the camera can recognize: person, animal, food, flower, sunrise and sunset, landscape and city (buildings / streets). When identifying the object to be captured, the camera app provides some filters that can be applied to the image. Using this feature, I managed to get some interesting results.

The Super Wide Angle (ultrawide) has 5 MP, f / 2.2 aperture, with 115 degree field of view. I liked it for bringing that feeling of shooting with a GoPro; noise can be slightly noticeable, however, it is possible to have beautiful images, especially of landscapes. It disturbs the distortions at the edges a little, but it is not at all glaring.

Sunset photo taken with LG K51S

Photo taken with the Super Wide Angle lens

Sunset photo taken with LG K51S

Photo taken with the Super Wide Angle lens

Landscape photo with LG K51S

Picture taken with the main camera

Image of a building made with the LG K41S

Photo of kitchen items made with the LG K41S

Photo of a tree made with the LG K41S

The LG K51S has a macro lens of just 2 MP with an aperture of f / 2.4 – don’t expect anything too amazing with it. At times, it doesn’t even look like you’re using a macro lens. Anyway, the specifications already deliver everything.

Photo of a flower taken with the macro lens

Picture taken with the macro lens

Coin photo taken with macro lens

Picture taken with the macro lens

The middle lens has 2 megapixels with an aperture of f / 2.4, exclusively for portraits. The quality, color and details are maintained, but it is flawed. There are times when the focus is blurred, blurring the shoulder and abdomen region.

The result in night shots can be very disappointing. I tested all the lenses, including the main one with Artificial Intelligence, but even that wasn’t enough for the K51S to deliver beautiful images:

Night shot with the LG K51S

Finally, the 13 megapixel front camera (f / 2.0 aperture) is very good. Although the blur is not so precise (again), I managed to get portraits with a good level of detail, vivid colors and no exaggeration with the embellishment mode.

Portrait made with the LG K51S

Hardware and battery

Like the K61, the LG K51S is equipped with a 2.3 GHz Helio P35 octa-core. It is the same processor as the Moto G8 Power Lite and some Huawei models. The GPU, in turn, is the PowerVR GE8320.

The processor can run everyday applications without crisis, such as Facebook, Instagram, Netflix and some light games. Do not expect brilliant performance, as it is not the strength of this model – nor the top of the line, if you are interested in it. The LG K51S even lost breath when working with various applications. There was slowness mainly when updating or installing a new app.

Call of Duty on LG K51S

The only app that closed unexpectedly was Spotify, it is! There are applications that can take a long time to open, especially heavy ones.

What’s more, the LG intermediary offers 64 GB of internal storage and 3 GB of RAM – another difference compared to the K61, which delivers 4 GB of RAM. It is worth mentioning that the K51S 64 GB memory can be expanded to up to 2 TB via microSD card.

Tray for adding chip and memory card

When it comes to battery, there are no complaints: they are 4,000 mAh, excellent capacity that does not leave the K51S behind the competition in this regard. With this, depending on the use, it will be possible to have a battery for up to two days, even with the maximum brightness.

During testing, I spent an hour watching video on YouTube (100% battery), 20 minutes of Asphalt 9 and another 20 minutes of Call of Duty, Netflix for three hours and social media for a few minutes. Result: there is still about 50% of battery left.

The LG K51S comes with a charger of only 10 watts, which means that you will have to leave the device for a long time in the socket. The smartphone reached its full charge in exactly 2 hours, a very satisfactory result.

LG K51S worth it?

Saying whether or not it is worth purchasing the LG K51S is quite complex. The advice I give is: analyze the specifications and see if it is worth disbursing R $ 1,500 to take the new K line intermediary, which does not deliver as many differentials as that.

LG K51S, cable and source

The differences from the other models are: the K51S comes equipped with a slightly more powerful processor than the K41S and a main camera of 32 MP.

Let’s do a quick analysis: the K51S arrived in Brazil with a suggested price of R $ 1,500 and the K61 for R $ 1,900 (hey!). However, I found the top of the line for sale in some e-commerces for R $ 1,700. So, if you liked the new handsets from LG and intend to buy, I advise you to add R $ 200 and take the K61, which, yes, has “significant improvements”.

Even though it doesn’t deliver as many differentials – which is very strange and here is my ear tug for LG – the K51S is an interesting device for bringing a photographic set full of features, beautiful design and long battery life.

LG K51S – technical form

  • Screen: 6.5 inch 20: 9 HD + Hole In Display
  • Processor: 2.3 GHz octa-core MediaTek
  • RAM: 3 GB
  • Internal storage: 64 GB + microSD up to 2 TB
  • Frontal camera: 13 megapixels (with Artificial Intelligence)
  • Rear cameras:
    • Main: 32 megapixels
    • Wide angle: 5 megapixels
    • Macro: 2 megapixels
    • Depth sensor: 2 megapixels
  • Drums: 4,000 mAh
  • Connectivity: Wi-Fi, Bluetooth 5.0, USB Type-C
  • Dimensions: 165.2 x 76.7 x 8.2 mm
  • More: fingerprint reader and Military Resistance certificates (resistance to impacts, humidity, vibration, operation and storage at high temperatures, operation and storage at low temperatures, thermal shock).



  • Quadruple camera
  • Powerful battery
  • Google Assistant button
  • DTS: X 3D Surround is a beauty
  • Super Wide Angle Lens


  • Macro camera sucks
  • Performance is poor
  • Loading time
  • Few differentials compared to the K41S and K61

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