Why should you dial *3001#12345#* on your cell phone if you have an iPhone and *#*#4636#*#* if you have an Android?

When we want to configure our mobile phone, whether Android or iOS, we generally do it from the device’s Settings menu. In it we can find (almost) all the parameters that we can adjust to adapt the operation to our tastes and needs. We can even activate a section for developers from which we can further control the phone’s settings. However, what many do not know is that these systems hide secret codes that we can execute to access settings that we otherwise cannot.

Both Android, and to a lesser extent iOS, allow us to configure almost whatever we want from our device. But there is one element over which we cannot have much control: the network and the SIM card. As a general rule, these two aspects are configured as standard to give the best possible experience to users, and are also usually controlled by each operator.

However, there are times when we need to change the network type, improve the signal, and even configure the SIM (change the PIN, etc.). And, for this, it is necessary to use the USSD secret codes. These codes, Unstructured Supplementary Service Data, are sent by the mobile phone directly to the operator’s network without doing anything else. In this way, it is the network that processes them and returns the corresponding response depending on what we are looking for.

The codes are different depending on whether we use Android or iOS. Let’s see what they are in each case and what we can do with them.

Run *#*#4636#*#* on Android

The first of the USSD codes that we are going to see is that of Android. To run it, we just have to open the phone keyboard and run the code on it. *#*#4636#*#*. By doing so, the signal will automatically be sent to the operator. And, in a few seconds, we will get an answer.

What we will see is that it is a “Test” section. In it we can access everything related to the device’s wireless connection, both in the data network and in Wi-Fi. If we have two SIM cards in the mobile, as is the case in this case, we can consult them and configure them individually.

If we enter our mobile network data, a screen will appear with a large amount of information. We can see the IMEI of the mobile, the phone number, configure the network type, boost the mobile signal to have better coveragemeasure the connection and more.

We can also access other information on the SIM card through the menu that appears at the top right of the screen. So, for example, we can see the service numbers, the phonebook saved in the SIM and more.

And there is not much more. This is an information panel from which we can also find some very interesting settings to improve our mobile signal.

iPhone secret code: *3001#12345#*

If you have an iPhone, we can also access a secret menu from which we will be able to obtain a lot of information about our mobile signal. In this case, the secret code that we must write on the iOS call keyboard is: *3001#12345#*.

As we can see, in this case it is a panel with much more information (or, at least, better organized) about our mobile signal. We can see all the data from the 5G and LTE networks, the data from the antenna to which we are connected and much more.

Of course, the configuration options in this case are much more limited, since it focuses only on displaying information related to the network.

Other secret network codes

In addition to the above, we can also know other codes that we can execute from our device to perform certain actions. For example, we have MMI codes, which have been present since the 2G era and which we can still execute. For example:

• *21*number# → activate call forwarding to another number.
• ##twenty-one# → deactivate call forwarding.
• *#31# → deactivate call hiding.
• *#06# → show the IMEI of the phone.
• **04*old-pin*new-pin*new-pin# → Change the SIM PIN.