Unlocking the Hidden Features: Top Smartphone Codes Every Android User Should Know

Usually, you control your smartphone or tablet via the OS or app menus. However, certain functions can only be accessed using control commands: these are combinations of numbers that you enter via your phone’s dialler app, just like a phone number.

Many of these functions are not actually intended for the user, but for the mobile network provider or service technician. That’s why very few are publicly documented.

You should definitely exercise caution when trying them out. In the vast majority of cases, the smartphone will simply display an error message if it doesn’t recognise the code. It’ll say something like, ‘Connection problem or invalid MMI code’. However, it may also crash, in which case the only solution is to restart it. Some particularly nasty commands can even wipe the smartphone.

Tip: Skip to the end of the article to see all the numbers and what they do.

Special commands for individual smartphones

Control codes that are executed directly on the device have been around for a long time. All you need to do is enter the digits into the smartphone’s phone number field for something to happen. The problem: most of these secret codes only work on certain models, and often only if they’re running a specific version of Android.

For example, the combination *#0*# opens an advanced service menu on a Samsung Galaxy model. This allows you to test the screen’s display to detect faulty pixels, for instance. Or you can check whether the phone’s vibration or orientation, light and accelerometer sensors are working.

Reading the device number on your smartphone

Every mobile phone and tablet with inbuilt mobile network hardware has a unique device number, known as the IMEI (International Mobile Station Equipment Identity). It’s worth knowing this number, as it’s the easiest way to identify your phone if it’s lost.

This works even if someone has since reset the device to its factory settings. Knowing the number also helps at the lost property office if you need to convince someone there that the mobile belongs to you.

Here’s how: The IMEI appears when you open the phone app and enter this code: *#06#. You can write down the IMEI or simply take a screenshot of the number and then send it to your PC or upload it to the cloud.

Viewing battery and system information on your smartphone

Entering the code *#*#4636#*#* takes you to an advanced information menu. Under ‘Phone information’, you’ll find a list of details about the device itself, such as the IMEI, which SIM provider you’re using, and your download and upload speeds.

On some devices (or some Android versions), you can also view ‘Battery Information’. This displays the battery temperature and shows the device’s operating time.

Under ‘Usage Statistics’, you’ll find details on which apps have been active and for how long. Finally, under ‘Wi-Fi Information’, you’ll find details on the status of the Wi-Fi connection and the configuration of the connected access point – for example, whether it uses DHCP and what encryption is used to secure the Wi-Fi connection.

Incidentally, the code also works without a SIM card inserted, as it communicates directly with the mobile phone.

Luke Baker

Android commands for the mobile network

If you enter a GSM or MMI code, the phone must be connected to a mobile network. That’s because these commands cause the smartphone to send a request to the mobile network provider to configure network-internal functions. For example, you can use #31# to prevent your number from being displayed when making calls. You can use other GSM codes to check your smartphone’s status for call forwarding when calls aren’t answered, when you’re unreachable, or when the line is busy.

Another example is the MMI code *#21#. This displays the current call forwarding status. Open the Phone app, enter the code *#21# and tap ‘Call’. The app will display the call forwarding status. Use the following commands to change call forwarding: set up with **21*, delete with ##21#, deactivate with #21# and activate with *21#.

As these codes are sent to your mobile network provider, it’ll depend on which commands each provider supports and which it doesn’t.

Don’t forget: GSM codes must be sent using the call button.

Communication via USSD (Unstructured Supplementary Service Data) commands works in a similar way: such numeric codes are frequently used on pay-as-you-go phones, for example to display the balance of the pay-as-you-go card.

Most USSD codes are specific to certain mobile network providers. For example, O2 customers can check their current bill amount for their tariff plan by dialing *140#.

It is essential to be cautious with Android codes, as they can pose security risks. USSD commands can be executed automatically if embedded as a link on a website using the ‘tel:’ command. This could lead to unintended actions such as changing PINs or resetting the phone to factory settings.

To protect yourself from such dangers, consider using security apps like NoUSSD to prevent automatic dialing of phone numbers from web browsers. Always be mindful of executing call commands and ensure to use the phone app for such actions.

There are various secret mobile phone codes that can be useful for different functions. For instance, *#06# displays the unique device identifier (IMEI), *100# shows prepaid credit for certain providers, and *140# reveals tariff details for O2 customers.

It’s important to be aware of these codes and understand their functions to make the most out of your mobile phone. Always exercise caution when using codes and prioritize security to avoid any potential risks. Transform the following:

Original: “I am going to the store to buy groceries.”
Transformed: “I will be going to the store to purchase groceries.”