One: First of all, look at the packaging. There are many introductions on the Internet. What I want to explain here is that when you take the mobile phone from the teller, it is best to keep the original packaging and let the teller treat you as When it comes to unpacking, there are currently two types of packaging, which are professionally called fragile seals or heat shrinkable film packaging. Generally, mid- to high-end mobile phone brands use heat shrinkable film packaging, which means that the entire mobile phone gift box is made of a layer of packaging. It is transparent and sealed like plastic wrap. Normal standard packaging will not have thorny burrs. The other is to put a sealing fragile sticker on the sealing area of ??the mobile phone gift box. It cannot be attached twice. If you find Being torn means that the machine may have been inspected by someone.

Two: The next step is to open the gift box and check the appearance of the host. Focus on whether there are detailed appearance scratches near the plug-in and pull-out interfaces such as the USB interface of the mobile phone and the four corners of the front. The checking distance is the distance you usually use the mobile phone 25- About 30mm. Take your white paper and insert it into the gap between the display and the frame on the front of the phone. If the phone can be inserted easily, it is best not to use it. Otherwise, the gap will easily accumulate dust, which will be difficult to clean and affect the appearance.

Three: Check the buttons. Press the power button, volume button, etc. naturally. You should feel that there is obvious rebound after pressing. Listen carefully and there is a ticking sound, which means the buttons have a good touch. If you feel that the button cannot be pushed down enough, the stroke is too short. Or it is best not to use a mobile phone that does not rebound much after being pressed

Four: Open the back cover of the mobile phone. If it has a removable battery, check three things:

1. Are the screws There are many machines that have slippage. Slippage means that the threads of the screws are damaged, and the screws have obviously been locked and opened many times. Such machines may have been repaired. Most mobile phone brands will have a sticker on individual screws to prevent counterfeiting before leaving the factory. Anti-tamper label

2. Whether the battery spring can naturally rebound when pressed down. If it cannot rebound completely, it may cause a passive power outage when the phone vibrates.

3. Label type: Whether the network access license and label are neat and legible. There should be a serial number IMEI in the battery slot. Write down this number for the next step of inspection

Just check items 1 and 3 for the built-in battery

Five: Dial and compare :

1. Plug in the available SIM card and memory card (not necessary if some mobile phones do not support expanded memory), plug in the battery and turn on the phone to see if you can make calls

2. Dial *#06# on the dialing keyboard, and a serial number will pop up, which is the IMEI number. Compare it with the number from the label on the back of the machine that you wrote down in the previous step. The authentic products are all consistent. If the phone is inconsistent, do not use it< /p>

Six: Check the camera:

Check whether the memory card is recognized in the phone settings. Open the camera and take a picture of the white paper with the entire lens to see if there are obvious spots of different colors on the picture and whether the outline of the person in the picture is clear

Seven: Listen to the sound:

Open a phone with a strong sense of movement Music or ringtones, turn up the external sound to the maximum, and listen to see if there is any obvious cracking noise

8: Take the mobile phone with the thumb and index finger of both hands (the mobile phone is facing away from you), use the thumb to gradually move from bottom to top Press the battery cover of the mobile phone and listen to see if there is an abnormal pressing sound. If there is an obvious sound, do not press it. It means that the mechanism design is not good or the mechanism may be repaired

Nine: Check the touch screen:

Open any picture or you can take it yourself. After enlarging the picture, try dragging the picture in the middle of the four corners of the display screen to see if you can drag it flexibly to check whether the touch screen is OK.

Ten: Finally, of course, check the accessories. Are everything in the list, such as the headphone data cable, etc., in good condition?