How to check a used Android phone when buying

How to check a used Android phone when buying

Many people prefer to buy used rather than new smartphones. On the one hand, such purchases allow you to save a lot of money, but on the other hand there is a chance to get a fully or partially defective device. However, you should not be skeptical of the secondary market for devices, because there you can find really high-quality models. To do this properly, you need to know how to check a used Android phone when buying. We propose to consider in detail what you should pay attention to in the first place.

10 tips before buying a used device

You should start choosing a smartphone right from home, using the sites of purchase and sale. It is categorically not recommended to buy any equipment from PawnshopsAs their employees often do not check the device from the viewpoint of operability. You can buy a device that looks fine, but has serious problems with the system. We recommend that you read the following tips carefully before buying a used phone:

  1. Choose your vendor carefully. When looking at ads, avoid those that are not written in broken language with a lot of mistakes. Most likely they are written by foreign scammers who do not have the machine specified in the ad.
  2. Don't agree to prepay. Some sellers, when communicating with you, ask you to transfer a percentage of the cost of the device to his account. As an argument, they present the fact that there is a huge queue for a smartphone, and to be the first, you need to show your ability to pay. Immediately stop the dialogue with such a personas in 99% cases it is a scammer.
  3. Avoid ads without a picture. Carefully see that the description of the product contains several pictures of it. If there are none, it is better not to start communicating with the seller, as there is a chance to lose time and run into a scammer.
  4. Do not consider phones with a broken screen.
  5. Avoid devices without a box and documents. If the ad says that the smartphone comes without documents and a box, then do not even think about taking this device. In this case, there is a chance of getting a stolen smartphone.
  6. To search for items Use only verified bulletin boards.
  7. Check the seller's profile on the sale and purchase website. Don't call the number listed in the ad right away. It is better to go to the seller's page and look through all his ads. If there are a large number of smartphones among them, it is better to avoid such an offer.
  8. Avoid offers with mail delivery. Only purchase goods in person.
  9. Do not consider ads with a suspiciously low price.


Following these tips you can choose a really good and reliable phone.

Checking the appearance of the smartphone

When meeting with the seller in person, feel free to examine the device thoroughly. If the person is in a big hurry, offer to meet him another time and test the device in a quiet environment. Often fraudsters reject such an offer, so be aware of this trick. In other cases carefully check the smartphone according to the following points.

Scuffs, chips, scratches

Checking your phone when you buy it handheld

The presence of a large number of scratches, chips or dents on the body can indicate long and careless use of the smartphone. Of course, such defects will not affect the operation of the device in any way, but you can demand a discount for them.

Particular attention should be paid to the rear and front camera module. It should be free of scratches, scuffs, chips and other damage. There can be no traces of moisture, dust or condensation under the camera glass. If there are any, it is better to refuse to buy a particular device.

Often unscrupulous sellers stick a protective film or glass on the display. In this way a person may be trying to hide defects, cracks and damage. It is not unreasonable to ask politely to remove the element that interferes with the examination.

When inspecting externally, try pushing on different parts of the case. If you hear a backlash or creak when you do this, it is possible that the smartphone has been disassembled.


A quality assembled unit will never make extraneous noises when in use.

Don't forget to bring a paper clip to open the SIM card tray. Carefully inspect the cavity and contacts for signs of oxidation. That way you can tell if the phone was in the water.

Inspecting back cover you have to be extra vigilant. It should not be crooked or contain bulges. If any defects are present, you are likely to buy a smartphone with a blown battery.

Broken pixels, yellow/blue spots on the screen

Check your Android phone for broken pixels and spots on the screen

It is not possible to detect broken pixels on the display with the naked eye. The easiest method is to use a white sheet of paper and your phone camera. Point the lens at the sheet of paper and take a picture of it. Then open the picture to the full screen. It is important that besides the white background there is nothing extraneous. Look closely at the display to make sure there are no black spots or smudges.

Dead Pixel Test
Dead Pixel Test
Developer: Ossibus Software
Price: Free

Of course, if you can, it is better to install a specialized application on your device. Dead Pixel Test.

Dead Pixel Test Android

The program alternately displays white, blue, gray, yellow, and red. Flipping is done by tapping on the screen. It is recommended that you carefully inspect every inch of the display. That way you will not miss any broken pixels or yellow spots. However, if they are detected, do not immediately sound the alarm. The manufacturer allows up to 5 damaged pixels on the screen.

Charging slot

How to check a used Android phone when buying

When meeting with the seller it is advisable to Bring a charging cable and a wired headset. Thanks to these accessories you will be able to check the connectors for looseness and functionality. If you are examining your phone in a place without power outlets, it is a good idea to bring a portable charger (Power Bank).

Carefully plug the cable into the charging slot and verify that charging has started. This may be indicated by a light on your smartphone or a notification on the status bar. Try moving the plug in the connector while paying attention to the charging process.


If, during this time, there are interruptionsthen it is better to refuse to buy this smartphone from hand.

Assessment of normal working capacity

Appearance is not a reason to refuse to buy a particular device. The most important parameter when checking is its correct and stable performance. We suggest that you read a practical guide on how to evaluate the main technical components of a smartphone.

Front and rear cameras

Camera test on Android phones when buying

First, start the mobile app that is responsible for creating the photos. If the meeting is outdoors, take some shots of far away objects. When examining the phone indoors, you can use a window. Such a test will allow you to check the quality of the camera, but not the presence of possible defects.

An ordinary white sheet of paper, which is better to take with you, will help you find the problem. Point the lens at it and take a few pictures. The image should be free of yellow, blue, green, and other stains. Also, if the camera is working properly, the white color will always stay that way, and not change to greenish or gray.

Sensors, BlueTooth, Wi-Fi, Mobile Internet

Checking sensor operation on a smartphone

It is better to start checking the technical component of the device with the sensors. Almost every modern phone has at least two of them: gyroscope and light sensor. To check the first one, start a video or watch a text. Alternately, turn your smartphone over carefully to observe the behavior of what's on the screen.


The text or video should change its position relative to the rotation of the phone. If it does not, the sensor may be defective.

Evaluate light sensor operability even easier. To do this, insert the SIM card into the device and make any call. While doing so, use your finger to close the sensor, which is often located at the top of the phone. If it works correctly, the smartphone screen will go out.

You can test BlueTooth by simply transferring a file from one device to another. Activate the function on the phone under test and select a document to send. If the sensor works correctly, the second device will display a window inviting you to accept the file.

It will be a little more difficult to determine if the Wi-Fi is working, because when you buy a device on the street, it will be difficult to find a stable source of Internet connection. When checking, you should pay attention to the speed of connection, the quality of connection, the stability of the connection. It is recommended to carry out the same procedure with Mobile Internetby installing your own SIM card in the phone.

Conversational and mainstream speakers

Conversational and main speaker on the phone

When checking a used phone when you buy it, you should pay attention to the audio system of the device. It is the quality of the speakers that determines the usability of the smartphone. The easiest way to assess the quality of the speaker is through a call. Put a SIM card in the device and talk to the person on the other end of the line. No extraneous noises, squeaks or other unpleasant sounds should be heard during the conversation.

As for the main speaker, it is better to use the app to check Speaker Test. The software allows you to evaluate the sound quality at different frequencies. Start the program and provide the necessary permissions, then select the desired frequency and click the "Play" button. Make sure that the volume is set to the maximum level.

Checking all documents and packaging

Check all documents and packaging when you buy a phone online

We recommend buying smartphones with an official warranty and box. This way you can somehow secure the deal and not fall for the tricks of crooks. Carefully check all the documents on the phone. It can't be the case that a Samsung device is for sale, but the warranty card lists Huawei. It's also worth checking the IMEI of the device against the numbers on the box. To do this, dial the combination *#06# at the call bar. The IMEI of the specific device will be displayed. Compare it with the one on the package. If they are different, it is most likely a stolen device.

Checking for originality

Many users mistakenly think that only devices of famous brands are counterfeited. However, this is not the case. Unscrupulous sellers can sell a copy of a cheap smartphone. To make sure that the phone is original, you need to perform simple checks.

By IMEI

How to check the authenticity of Android by IMEI

The IMEI check is the easiest way to verify the originality of the device. IMEI is a code that is assigned to the device when it is assembled at the factory. It often consists of 15 digits containing the following data:

  • The first six digits are the batch number;
  • The next 2 digits are the manufacturer's information;
  • The next six digits are the serial number of the device;
  • The last digit is a unique code of the phone, indicating its originality.

As written above, to find out the IMEI of the device, you need to enter the combination *#06# and press the call button. A window will appear on the screen, where the smartphone's IMEI will be shown. Then you need to check the code with the data on the box, in the warranty card and under the battery cover (if it is removable). If the IMEI matches everywhere, then go to the official authentication sites of the manufacturers:

We propose to consider the verification procedure on the example of a smartphone Xiaomi:

  1. Open the official Xiaomi website to verify the authenticity mi.com/global/verify/.
  2. Choose the first tab to check the originality.
  3. In the input field, enter the IMEI or serial number of the device.
  4. Enter the captcha.
  5. Press "Verify".

If the smartphone is genuine, a green checkmark will appear on the display.

By serial number

How to check your Android phone by serial number

Checking for authenticity by serial number is almost no different from checking by IMEI. This code is located on the box, and marked with the letters SN. To do this, you can use the official sites of the manufacturers, or install the Antutu application. Let's look at how the program works:

  1. Open the app.
  2. We provide the necessary permits.
  3. Press the button "Checking the device".
  4. Waiting for the end of the procedure

If the phone is original, a message will be displayed on the screen with the text "Genuine.". Thanks to the Antutu program you can check absolutely any Android smartphone for authenticity.

Video tutorial

To summarize, a used phone should always be checked before buying. This applies to both iPhone and Android. So you can identify external defects, understand the technical condition of the device and negotiate a discount.