Modern smartphones Xiaomi, Redmi and POCO They store a huge amount of sensitive information, from banking applications to personal photos, a standard pattern lock or a standard pattern lock. PIN-It's often not enough to provide fast but reliable protection, and that's why biometric authentication becomes the standard, allowing you to access a device in a split second with a simple touch.
Turning on the fingerprint scanner is not just a matter of convenience, but a necessary step to improve the security level of your gadget. Many users mistakenly believe that the system is set by default, but there are subtle settings in the shell of MIUI and the new HyperOS that allow you to use your finger not only to unlock the screen, but also to hide the content of notifications or log in to applications.
In this article, we will take a look at the entire process of activating biometrics, from initial setup to fixing common problems, learn how to apply your finger correctly for maximum read accuracy and what additional safety features you should activate immediately after you turn on the scanner.
Preparation of the device for setting up biometrics
Before you go directly to the scan, you need to make sure that your device is ready to work with biometric data. First of all, the phone must have a strong digital password, a pattern lock or a complex unlock code. Android requires a backup authentication method in case the scanner cannot recognize the fingerprint or the device will restart.
It's also worth checking the surface of the scanner. If your device has a sensor built into the on button (side scanner), wipe it with a soft cloth. For models with a subscreen scanner, it's important to make sure that the protective glass is not damaged at the bottom of the screen, where the reading area is usually located.
⚠️ Warning: Do not try to stick thick protective glass or use covers covering the scanner area immediately after setting up.This can lead to a decrease in read accuracy or complete inoperability of the function.
Make sure the operating system is updated to the latest available version. From the Settings menu → About the phone, check for updates. Xiaomi developers regularly release patches that improve sensor algorithms and fix bugs in the security module.
Step-by-step activation of the fingerprint scanner
The process of enabling biometrics in the MIUI and HyperOS shells is almost identical, although the item names may differ slightly. To begin, open the main settings menu of your smartphone. Find the Passwords and Security section (in some versions it may be simply called “Security” or be inside the “Additional” menu).
In the list that opens, select Unlock by fingerprint, and the system will prompt you to enter your current password or graphical key to verify your identity, a mandatory security measure to prevent unauthorized individuals from changing biometric data.
Once you confirm your password, you'll see a screen with the instruction and the Add fingerprint button, and click on it to start the scanning process, and you'll see a schematic picture of your finger that will fill in as you read it.
Put your finger on the scanner (repeatedly), changing the angle of inclination slightly each time, and the system must read not only the center of the pad, but also the edges of the pad, which is critical for the precise operation of the sensor in the future, when you hold the phone in different positions.
Fine tuning and additional functions
After successfully adding the first print, the system will offer to expand the functionality of the biometrics. The fingerprint management menu often features the option “Unlock in the off screen”**. Make sure that this switch is activated, otherwise you will have to first touch the screen to activate the sensor, which negates the convenience of the function.
Another useful feature is Hiding content when notifications are received on a locked screen, and if this option is enabled, the text of messages from messengers will be visible only after successful authentication with your finger, which protects your correspondence from curious glances on public transport.
Why do you need multiple fingerprints of one finger?
Adding the same finger under different names (e.g., "L finger" and "L finger 2") allows the system to create a more complete fingerprint profile, which greatly increases the unlock speed if the standard scan is error-prone or requires re-attachment.> For users who value maximum privacy, Private Safe or Second Space is available, and you can only access hidden files or a separate user profile through a specially registered fingerprint other than the main one. Description Where to find Unblock Access to the desktop Settings → App Lock passwords Protect individual applications → Block. Appendix. Private Safe File Confider → Payment Confirmation of Transactions Settings → Fingerprint Using a fingerprint to protect applications One of the most popular features of the Xiaomi ecosystem is the ability to set a password to run specific applications. You can protect access to the gallery, banking applications or messengers by requiring fingerprint confirmation each time they are opened. To activate this function, go to the Security application (green icon with a shield), which is preinstalled on all smartphones of the brand. In the lower menu or in the tool list, find the Lock block item (App system asks for a graphical switch from the menu. Now, when you try to open a secure app (marked with a lock on the list), the phone will request biometric confirmation, which creates a double layer of protection: even if someone can unlock your phone, they will not be able to log into critical programs without your finger. This is especially true if you lose your device or temporarily access your gadget. 📊 Where is the fingerprint scanner on your Xiaomi?In the side button, under the screen (optical)On the back I have Face ID Despite the high accuracy of modern sensors, users can face situations where the phone no longer recognizes the finger, most often due to contamination of the sensor surface or hands. Fat, moisture or dirt distort the pattern of papillary lines, making reading impossible. If the problem isn't dirt, try reconfiguring the fingerprint. Delete the old profile in the settings and create a new one with a special focus on the edges of the finger. Sometimes it's helpful to add the same finger twice as different profiles (e.g., "Finger 1" and "Finger 1 copy"), which will increase the scanning area. ⚠️ Attention: If the scanner stopped working after falling or getting moisture, do not try to dry it with a hair dryer. Hot air can damage the adhesive layer of the display or the sensor itself. Let the device dry naturally. In rare cases, the problem can be software. Rebooting your device often helps to reset driver errors. If that doesn't work, check if you have custom recovery or modified firmware installed that may conflict with the security module. TEE (Trusted Execution Environment). Many users are wary of storing their biometrics in their phone’s memory, but in Xiaomi devices, like most smartphones today, fingerprints are not stored as images. The system converts them into a unique digital hash code that is encrypted and placed in an isolated secure module of the processor, and even when you connect the phone to the computer in debugging mode or when you try to hack the system, you can't access this data. They are not transferred to Xiaomi, Google or third parties, and when you reset your phone to the factory settings (Wipe Data), these keys are permanently deleted. 💡Biometric data is only stored locally in encrypted form and never leaves your device, which guarantees its privacy. However, it's worth remembering the legal aspect: unlike a password, which you can not disclose, a fingerprint can be forcibly seized in a number of jurisdictions. So, to store sensitive data, it is recommended to use complex alphanumeric passwords in addition to biometrics. Can I add a fingerprint of someone else? Yes, technically, the system allows you to add up to 5 different fingerprints. You can register a finger of a spouse, child or a trustee. However, this reduces the level of security, since any of the added users will have full access to the device. Why does the scanner not work with gloves? Optical and capacitive sensors require a direct contact with a penclogging cloth. Some ultrasonic scanners (found in flagships) can work through thin fabric, but on Xiaomi mass models this is not possible. Does glued glass affect the scanner? For side scanners, quality glass does not affect the work. For underscreen scanners, the thickness and quality of the glass are critical. Cheap thick glasses or glass with a black frame that overlaps the scanning area can make the function useless. It is recommended to use special glasses for underscreen scanners. What to do if the print is erased? For some people, the thickness and quality of the glass is critical from nature, and the glass is less of the finger, or the use of a large finger, for example, or a large finger with a large one from such a finger.