Used and Refurbished Cell Phones

Used & Refurbished Cell Phones

Buying a used Android phone is something that is a big challenge for many users and causes a certain fear. Despite that, it is known that today most people decide to buy a used phone rather than a new one. Why would anyone buy a used phone sooner than a new one? The most common reasons for this are a less favorable financial situation or simply high profitability, considering that in principle a well-preserved used phone is much cheaper than a new identical phone.

So it is not uncommon for a very little used high-end phone to be cheaper than a new lower-end phone, and very likely without sacrificing any functionality. For this type of user, various shopping sites are a refuge where it is possible to see anything and everything, including potential fraud attempts.

Since testing the correctness of the used phone is not the easiest task, the instructions explain what you can pay attention to when inspecting the device.

As a criterion for selecting components for inspection, we used the frequency of failures and the objective possibility of quick inspection, with the fact that failures on other components are also possible and for some failures it takes a few days to establish, sometimes even more.

Also, note that the above in the article can happen to new phones.

First of all, insert the appropriate SIM card and memory card, if supported by the device.

Exterior appearance
The first thing that is visible when the phone is picked up is - the phone itself. Pay attention to the components of the phone, specifically whether the parts of the cover of the device fit evenly on all sides, because if something is air-conditioned or something is wrong on one side, it is a possible indication that the device has been serviced.

Next, remove the battery cover and pay attention to the screws. If all the screws are not the same and there are certain deformations on them due to the use of a screwdriver or screwdriver, there is a high chance that the device was once opened for servicing.

Next in line is the screen. Before turning on the screen itself, we will start with a dust inspection. See if there is dust between the touch glass and the screen of your potential Android. Some crumbs are not an alarm signal, but if there are more crumbs on different sides of the screen, it is very possible that the device was opened and the screen or touch glass (digitizer or just "touch" below) was changed.

What is the cause of that? Each phone around the screen has a protective layer of thick adhesive insulation underneath, whose role is to hold the screen and touch together, as well as to prevent dust from penetrating into the space between the screen and the digitizer. Otherwise, this layer is difficult to see because it is hidden under the part of the touch that is not transparent. When removing the screen or digitizer, this layer cracks in 99% of cases, and when servicing is done, in most cases the service technicians do not put a layer of glue over the cracked parts to repair the inevitable damage but simply return the parts without worrying about cracked parts of the layer. increasing accumulation of dust.

Now let's go to the screen ignition and inspection. Since not all screen types are the same and have different properties, we will deal individually with the types of screens that are most commonly seen on phones.

AMOLED screen

The much praised but also criticized AMOLED screens are really beautiful to look at, the colors are bright and sharp and they are most famous in Samsung phones of the highest class such as Samsung Galaxy S all the way to Samsung Galaxy S5. However, some write them a minus because of the display of color shades that are not close to reality but are overemphasized. When using a device with an AMOLED screen, it is necessary to pay attention to several things, and most of all to something known as burn-in.

Remaining occurs when the same image is on the screen for a very long time, so over time, the notification bar at the top of the screen, as well as the icons at the bottom of the home screen, are usually retained. Basically, you can fry everything that is almost constantly present on the screen when using the phone in the long run. Luckily in an accident, all this can be seen the most when there is something of a uniform color and shade on the screen. Not to complicate the explanations, you will understand most quickly if you look at the example of Samsung Galaxy S in the video below, the screen shows gray "ghosts" icons that are otherwise present on the home screen and instead of "ghosts" should be only white as on the rest of the screen .

To test if your AMOLED screen phone has any support, transfer the following images to the phone you are testing and open them in full screen. Make sure you inspect at the lowest and highest light levels.

Classic LCD screen

These screens are loved by everyone who prefers a proven old school, realistic color rendering and would like to avoid the burn-in that is inherent in AMOLED screens. These screens are characterized by a clean and faithful display of colors and with the advancement of technology, the display has become far more pleasing to the eye.

With classic LCD screens, the most common irregularities are in the form of dead pixels. Dead pixels are black dots on the screen itself, and they can also be green dots, but then they are visible only if there is something very dark or black on the screen. If there aren’t a lot of them, it’s not a problem but the situation changes if there’s a whole army of dead pixels there. What exactly it is about can be seen in the following pictures that we have set as an example. Click to enlarge.

Touch (digitizer)

For touch testing, it’s best to get into any app that requires the use of a keyboard because touch most often shows signs of wear at the bottom of the screen occupied by the keyboard. Click on each symbol on the keyboard and pay attention to irregularities in the form of marking the wrong letter (eg the letter K is typed even though the letter L is touched, see picture) or even worse not recognizing the touch. Simply check the top of the screen by touching the options on it. Please note that touch faults may be periodic in nature and may not be noticed immediately. The figure below shows what has just been shown and the area that was touched at that moment is marked in red.

When you start the camera, try to turn the device towards something that is uniform white, because that is when certain irregularities in the camera lens itself are best seen. Plain A4 paper or even a house wall can also be used for this purpose. Then pay attention if there are any irregularities in the picture in the form of darkened freckles, etc. Also try the flash if the device has one.

The same is true for autofocus, except that two images should be taken for the autofocus test. In the first picture there would be an object a few inches from the camera (macro), and in the second picture there would be something very far away. This is done because on some devices it may happen that the autofocus works at close range and not at a distance and vice versa, which certainly results in blurry images, which is an irregularity that you would not want.

The handset above the screen you use for talking can be easily checked. Before you start anything, make sure there is no dust on the handset. Then call someone or even one of the phone numbers that your answering machine will answer. Such numbers are most often operator support numbers. In doing so, turn up the volume on the headset to the end and press it to your ear, if you hear a squeak or the headset is too quiet, it is a sign that it is probably time to service it. Also see if the screen turns off after touching the ear (if the device has a proximity sensor).

If possible, you could also talk to someone along the way to test the microphone.

External speaker
There’s not a lot of philosophy here either. Start a song, turn it up to the end and assess if there is any squeaking or too low volume.

You will probably need another bluetooth device for this. Turn on the bluetooth on both devices, move them at least 60 cm apart and then turn on the search for bluetooth devices nearby on the test device. If this other device is detected, it means that bluetooth is working. It would be advisable to try to transfer some smaller file, of course respecting all of the above.

And this is simple. Make sure you are in a place where there is at least one Wi-Fi network and that you are not close to a router. If one or more Wi-Fi networks are found, the Wi-Fi component works. It would be advisable if they could connect to one of the Wi-Fi networks nearby and then run any internet browser in the phone.

Headphone jack
To test the headphone jack, it is recommended to use headphones whose connector has 2 rings. Headphones of this type are most often non-purpose headphones, ie. headphones that are not adapted to devices of a particular brand. If you have headphones with 3 rings, they can also fulfill the purpose, although sometimes they do not have to match the tested device, since such headphones are sometimes adapted to a certain brand, so there is a possibility of malfunctions if used with other brands.

The testing itself is very simple: start a song with the headphones on, see if the sound is neat, that there are no irregularities and that's it.

USB and charging port
This is easy to do as long as you have a charger and socket nearby. One side of the charger into the phone, the other into the socket and monitor whether the phone has started charging. Leave it to charge for about 30 seconds.

Memory card
This can be checked in several ways. One is to navigate to Settings -> Storage where the memory card you previously inserted should be read.

When buying a used Android phone, it is recommended to read the warranty conditions in detail for several reasons, assuming that the device has a warranty.

First, read what the warranty conditions are, because often parts such as the screen, speakers and other hardware components of the phone are not covered by the warranty, so in that case you actually only have a warranty on the software. Also, pay attention to the date of purchase, warranty period and stamp.

Secondly, make sure that the IMEI number of the phone matches the IMEI number written on the warranty, because without that the warranty cannot be accepted. The IMEI of the phone can be easily found out in 2 ways.

- The first is to read what is written under the battery of the device.

- Another way is, of course, while the phone is on, click on Dialer, (same as when you want to call a number), enter * # 06 # and the IMEI number will be displayed.